witt sys iom

28
THE GUIDE FOR INSTALLING, STARTING - UP, OPERATING and MAINTAINING WITT CONDENSING UNITS AND REFRIGERATION SYSTEMS TABLE OF CONTENTS Safety Information and Guidelines.....................................................…….....2 Receiving and Handling ................................................................……….......2 Locating and Mounting Condensing Units ....................................………....3 Locating and Mounting Evaporators........................................……...........4 - 5 Piping ...............................................................................................…….........6 - 7 Leak Testing .................................................................................…...……......7 Suction Line Design ...............................................................….….…............8 Equivalent Feet of Tube ........................................................……............... 9 Weight of Refrigerant in Copper Tube........................................….…........9 Recommended Line Sizes ..........................................................…….…....... 10 - 13 Field Wiring.....................................................................................…….......... 14 Field Wiring Diagrams .................................................................……..…...... 14 - 16 Evacuation .................................................................................…….…..........17 Charging and Start-Up .................................................................…….….......18 Charging Flooded Condenser Systems ......................................………...19 Pressure Control Settings ...............................................................………....20 Indoor Condensing Unit Ventilation ................................................………...20 Defrosting Evaporators .....................................................................…...…...21 - 22 Product Loading and Air Circulation ................................................….…....22 Operating Pressures and Temperatures .......................................……...…..23 System Start-Up Check List ...........................................................…...…..... 24 System Service Check List ...........................................................………......25 Trouble-Shooting Systems ............................................................……......... 26 - 27 System Maintenance .....................................................................……..........28 Ordering Replacement Parts .......................................................………....... 28 SYSTEMS IOM W550.0 January, 2002 201 Thomas French Dr. Scottsboro, AL. 35769 Phone 256-259-7400 Fax: 256-259-7478

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Page 1: Witt Sys Iom

THE GUIDE FORINSTALLING, STARTING - UP,

OPERATING and MAINTAINING

WITT CONDENSING UNITS AND REFRIGERATION SYSTEMS

TABLE OF CONTENTSSafety Information and Guidelines.....................................................…….....2Receiving and Handling ................................................................……….......2Locating and Mounting Condensing Units ....................................………....3Locating and Mounting Evaporators........................................……......….....4 - 5Piping ...............................................................................................…….........6 - 7Leak Testing .................................................................................…...……......7Suction Line Design ...............................................................….….…............8Equivalent Feet of Tube ........................................................…….........…...... 9Weight of Refrigerant in Copper Tube.................................….......….…........9Recommended Line Sizes ..........................................................…….…....... 10 - 13Field Wiring.....................................................................................……..........14Field Wiring Diagrams .................................................................……..…......14 - 16Evacuation .................................................................................…….…..........17Charging and Start-Up .................................................................…….….......18Charging Flooded Condenser Systems .................….....................………...19Pressure Control Settings ...............................................................………....20Indoor Condensing Unit Ventilation ................................................………...20Defrosting Evaporators .....................................................................…...…...21 - 22Product Loading and Air Circulation ................................................….…....22Operating Pressures and Temperatures .......................................……...…..23System Start-Up Check List ...........................................................…...….....24System Service Check List ...........................................................………......25Trouble-Shooting Systems ............................................................…….........26 - 27System Maintenance .....................................................................……..........28Ordering Replacement Parts .......................................................………....... 28

SYSTEMSIOM W550.0

January, 2002

201 Thomas French Dr. Scottsboro, AL. 35769 Phone 256-259-7400 Fax: 256-259-7478

Page 2: Witt Sys Iom

SAFETY INFORMATION

READ THESE INSTRUCTIONS ALL THE WAY THROUGH BEFORE STARTING WORK!

Make sure all power sources are disconnected before doing any service work. LOCK disconnects in the OFF position to prevent accidental turning on and injury.

Commercial refrigeration equipment should be installed, started-up, maintained, andserviced by trained and certified personnel having experience with this type of equipment.

All field wiring must conform to the requirements of the equipment, applicable localcodes and the National Electrical Code. Always use correct size copper conductors.

Sheet metal and coil surface have sharp edges that are a potential injury hazard.Handle carefully, using gloves and other protective safety wear to prevent injury.

COMPLY WITH SAFETY AND CAUTION LABELS ON THE EQUIPMENT

THINK SAFETY ! WORK SAFELY !

RECEIVING YOUR EQUIPMENT

INSPECTIONCheck all items against the bill of lading to make sure all crates and cartons have been received.If there are any shortages or damage, report it immediately to the carrier and file a freight claim.Damaged equipment is the delivering carrier's responsibility. Take care not to damage equipmentwhen uncrating. Check for concealed damage. Do not return damaged equipment to the factory without prior approval. A Return Material Authorization (RMA) must be obtained in advance.

Check the unit specplate. Verify that the specplate voltage agrees with the available power supply.Large condensing units, remote condensers, and evaporators should be left on their shipping skiduntil at their final location. Do not use the shipping skid as a permanent base.

RIGGING and HANDLINGGood rigging and handling practice must be used to protect units from damage. Having properhandling equipment at the jobsite is most important and should be planned in advance. Always usespreader bars when lifting with cable, chain, or slings. Do not hoist a crate from it's upper members.If rigging is required, support the crate from the skid. All crates are blocked up for forklift handling.Do not forklift against sheetmetal panels or coils. Always lift against a structural part of the skid orunit at the center of gravity. Secure units to a forklift to prevent slipping off.

Large condensing units have compressors mounted near one end that offsets the center of gravity.Find the center of gravity near the compressor end to prevent tipping when lifting. Smaller, lighterunits may be carefully manhandled for short distances. Observe the units for additional lifting andrigging decals.

2

« « « « Items returned without an RMA label will be refused . « «« «

Page 3: Witt Sys Iom

3

LOCATING AND MOUNTING CONDENSING UNITS

Condensing units must be located where there is anunrestricted supply of clean, fresh air. Areas with corrosive vapors or materials should be avoided, asshould areas with polluted air. Do not locate unitswhere air discharge from one will enter into the airintake of others. Avoid locating units in restrictedspaces where heat will build up and can enter thecondenser. Condensing units with horizontal airflow should be positioned so that the direction of airflow through the condenser is the same as the prevailing wind. Make sure there is room aroundthe unit for regular inspection and service. Mountall condensing units level.

Roof mounted condensing units must have adequate support for their operating weight plus asafety factor. They should be mounted above supporting walls, over hallways, storage areas, orauxillary areas that are not sensitive to noise or vibration. Mount them where sound levels are not an important factor.

Pad mounted condensing units should be mountedon smooth and level pads a minimum of 4 inchesabove ground level. They should be mounted away from windows, doors, and other areassensitive to noise. The area surrounding a padmounted unit preferably will be concrete, asphalt, orother smooth, hard, clean level surface. This will keep the condenser coil clean from grass, dirt,and weed clippings. A security fence also helps tokeep leaves and other debris out of the coil. Protecting the condensing unit also protects theproduct stored in the cooler or freezer!

Condensing units, piping and disconnects shouldnot be accessible to unauthorized persons. To protect the equipment from tampering and vandalism and protect people from accidental

injury, a security fence with locked access is highlyrecommended. Condensing units accessible to thegeneral public often receive damage to the coil, piping, fans, or other components. Protect your equipment, your products in storage, and protectyourself from liability. Prevent accidents and loss.

Condensing units must be mounted to pads or structural rails with adequate size bolts to preventthe unit from shifting or changing postion.Mounting holes are provided for proper size fasteners. Iso-pads are recommended to absorbvibration and reduce noise. Seismic isolators maybe required in some localities. Follow the isolatormanufacturers recommendation when selecting andapplying isolators. Mount units level.

Condensing units with spring mounted compressorsare shipped with blocks or retainers under the compressor feet to keep it from shaking during shipment. On Copeland H and K modelcompressors, remove the blocks and loosen themounting nut to have 1/16 inch between the nut andrubber spacer. On 3 HP and larger models, mounting nuts must be removed to insert the rubber spacer. Remove the blocks, insert the rubber spacer over the mounting stud, replace thenuts and tighten to 1/16 inch from the spacer. Donot tighten mounting nuts tight against the rubberspacer or foot. Units with iso-pad mountedcompressors are shipped with the mounting nutstight and they should be checked to be sure theyhave not loosened in shipment.

Observe minimum clearance recommendations below. Do not locate any unit to be bordered by tallwalls or obstructions on three or more sides, evenwhen the clearance are observed. The minimumspace between units is 2x dimensions shown.

Table 1

CONDENSING MINIMUM

UNIT DIMENSION (Inches)DESCRIPTION A B C

Proline 1/2 thru 2 HP 60 24 36

Proline 3 thru 6 HP 72 24 36

WD Series 3 thru 22 HP 72 30 48

WV Series 20 thru 80 HP 48 48 48

B

CONDENSING UNITDISCHARGE AIR INTAKE AIR

A C

B

Drawing 1

Page 4: Witt Sys Iom

12" 12" 12" 24" 60"15" 15" 15" 30" 75"18" 18" 18" 36" 90"24" 24" 24" 48" 120"30" 30" 30" 60" 150"36" 36" 36" 72" 180"42" 42" 42" 84" 210"48" 48" 48" 96" 240"

* Critical Minimum Dimension H = Height of Evaporator ‡ Minimum walk-in height of 7'-0"

Air H

Front wall5 x H Min.

12"

Air Product

Product Storage Area Door

* Refer to Table 2 for dimension H Floor

Drawings are not to scale

No doors at side or back of evaporators. Back wallH

H 2 x H H

Side Evaporator

wall

Air Air

5 x H SideAlternate wallDoor location

* Refer to Table 2 for dimension H Door Front wall

4

SIDE VIEW

TOP VIEW

Evaporator

126" 144"

3 x H

Evap.

ObstructionFreeArea

60" ‡72" 90" 108"

60" ‡60" ‡

Unit toFront Wall

5 x H

Unitto Floor3 x H

Unitto Unit2 x H

LOCATING WALK-IN EVAPORATORS

AND EVAPORATOR PERFORMANCEMINIMUM DIMENSION FOR GOOD AIR CIRCULATION

EVAPORATORHEIGHT (Key Dim.)

H

Unit toBack Wall *

1 x H

Unit toSide Wall

1 x H

Table 2

Page 5: Witt Sys Iom

Locate evaporators for the air pattern to cover all of the piping, and personnel. Heavy zinc plated or stainlessroom. Do not restrict the inlet or outlet air stream. steel bolts should be used to mount evaporators. WeAvoid placing evaporators above or close to doors. recommend a minimum 5/16" diameter for Super-Flo, Direct the air stream toward the door when possible Easy-Flo and Dual-Flo units. A minimum 3/8" diameteror arrange to blow down an aisle. Allow sufficient should be used with Inter-Flo and Polar-Flo units. clearance for air circulation and servicing the unit. Use flat washers next to hanger bars and tighten all fasteners

securely. Hang all unit coolers level to insure positive The ceiling structure must have adequate strength to condensate draining. All drain lines must be trapped.support all mechanical equipment, components,

Drawing 4 Drawing 5

Air

Air

2 x H* 2 x H*

EVAP.

AirEVAP.

Air

TOP VIEW - Large coolers or freezers where one wall will not accommodate all evaporators or desired air throw is excessive.

Drawing 6 Drawing 7Air

A C

EVAP. B EVAP.A A

C

Air Air D

Air Air

CAir

TOP VIEW - Single Centermount Unit

Min. Min. Max. Max. Min. Max.1' 2' 16' 12' 8' 24'

Dimensions are in feet. One foot minimum between bottom of unit and top of product.

5

LOCATING AND MOUNTING WALK-IN EVAPORATORS

RECOMMENDED SPACING FOR CENTERMOUNT EVAPORATORS

*Refer to Table 2 for dimension H

D

EVAP.

See Table 3 See Table 3

TOP VIEW - Multiple Centermount Units

8' 3'

Table 3Max. Min.

A B C

Page 6: Witt Sys Iom

PIPING

Condensing Unit and Evaporator coils are thoroughlycleaned and dehydrated at the factory. Care must betaken when field piping to prevent foreign materialsand moisture from entering the system. Do not leaveunits or piping open to the atmosphere any longerthan necessary. Use ACR grade Copper tube, keeping it dry, clean, and capped. If type “L” tube isused, it should be thoroughly cleaned internally.When brazing, always pass dry nitrogen through thetubing to prevent oxide and scale from forming. Asuitable silver alloy solder should be used on suctionand liquid lines. Use only Wrot Copper fittings. Longradius elbows should be used. Install all piping andcomponents in accordance with local and nationalcodes and in conformance with good refrigerationpractice for proper operation of the systems.

The suction line and its components must be selectedand installed with extreme care. The suction linemust be sized for high enough refrigeration velocity toassure good oil return, and low enough pressure dropto prevent excessive system capacity loss. The optimum line size for a system will result in areasonable velocity at minimum pressure drop. Totalsuction line pressure loss should not exceed 2°Fequivalent loss.

Suction line risers must be carefully selected, havean oil trap at the bottom and at 15 foot intervals upthe riser. The should be the same size as the verticalriser connected to its outlet. Riser should not belarger in diameter than horizontal runs.

Horizontal runs of suction line should slope 1 inch per10 feet in the direction of flow. A 1/4 inch male flareSchrader fitting should be installed in the suction lineat the evaporator outlet to obtain accurate evaporatorpressure and superheat readings. Refer to pages 8though 13 for line size recommendations and pipingdiagrams. Note the maximum size for suction line risers.

Liquid lines, both horizontal and vertical, are normallythe same size. In vertical lines with upward flowthere will be a pressure loss similar to that in waterline riser, due to the lift involved. If ignored, this pres-sure loss can result in liquid line flash gas that will prevent good expansion valve and system performance. Sizing the liquid line too small will alsoresult in flash gas. Sizing a liquid line larger than

necessary will increase the system refrigerant charge.Flash gas can be avoided by adding subcooling tothe system, however, subcooling should not be considered as an acceptable alternative to properlysized liquid lines.

One method to obtain liquid subcooling and returngas superheat is to join the liquid and suction linetogether and then insulate them. This economicalmethod is often used on vertical lines. Anotheralternative is to use a manufactured liquid-suctionheat exchanger. This type of heat exchanger is usually located inside the cooler or freezer, near theevaporator. D series and V series condensing unitsinclude an integral liquid subcooling circuit in the condenser coil. Any one of these methods will normally provide enough subcooling to offset the liquid line pressure loss due to friction and lift. Liquidlines with more than 30 feet of vertical lift need special attention!

A liquid line solenoid should be installed near theexpansion valve inlet. If there are multiple evaporators, locate the solenoid near the branch lineto the first evaporator.

Before installing the expansion valve on thedistributor, check the distributor to be sure it hasa nozzle installed or is a venturi type. For optimumperformance, the expansion valve outlet should beinstalled directly to the distributor. If reducing couplings or adapters are required keep them closecoupled. Do not have elbows between the expansionvalve and distributor. The expansion valve must beselected to match the system capacity. Follow theexpansion valve manufacturers ratings when select-ing the valve and use the appropriate capacity multi-plier if liquid is subcooled below 70°F. If the amountof liquid subcooling may vary, a balanced port expan-sion valve should be used.

Evaporators with 1/2 inch flare nut (FN) inlet distributors can be converted to a sweat type inlet.All distributors have room to remove the flare with amini-cutter. The inlet would be 1/2 inch OD and anexpansion valve with 1/2” ODF outlet would fit. Alcotype HFS or Sporlan type EG, SBF or S expansionvalves are available with 1/2” ODF extended Copperoutlet connections. To protect the valve(s), wrapthem with a wet rag while brazing. Disassembly ofthe valve is not required.

6

Page 7: Witt Sys Iom

Expansion valves are supplied with clamps for securing the bulb to the suction line. The bulb mustbe secured at the evaporator outlet, on the side of ahorizontal run of suction line, at the 4 o’clock or 8o’clock position, before any traps. The bulb must bein uniform contact with clean Copper tube and mustnot bridge any fitting or uneven surface. A thermalmastic or heat transfer compound may be used withthe expansion valve bulb and suction line for quickerexpansion valve response. DO not overtighten bulbclamps or deform the bulb in any way.

Drain lines should be the size of the evaporator drainpan connection or larger. They should not be reduced in size. Plastic drain lines are often used incoolers, however, Copper or metal lines are recommended if room temperature is below 35°F. Alldrain lines must be protected from freezing. All drainlines must be trapped and run to an open drain.Drain lines should be sloped 4 inches per foot toinsure positive drainage. Never connect a condensate drain directly to a sewer line. Neverdrain onto a floor or walkway, creating a safetyhazard. Traps must be in warm ambient or be protected from freezing. It may be necessary to runheat tape the entire length of the drain line and trapto prevent freezing. Insulating the drain line is recommended with the heat tape energized continuously. Drain properly and safely!

All piping must be adequately supported to preventvibration and breaking. Tube clamps should have agasketed surface to prevent abrasion. Inspect all piping while the equipment is operating and add supports to prevent stress and vibration. When theliquid solenoid opens and closes, the liquid line will

tend to move forcefully. Without proper support thejoints at the liquid solenoid, expansion valve, distributor, and distributor leads can fracture. Takecare to secure the liquid line at the evaporator. Linesupports are inexpensive compared to downtime andrefrigerant loss. All piping must be protected whereit passes through walls or ceilings. Precautionsshould be taken to see that the piping does not touchany structural members and is properly supported inorder to prevent the transmission of vibration into the building. The piping chase must be thoroughlysealed to protect the tube and prevent ambient airfrom entering the refrigerated space. Seal aroundthe drain line where it passes through the wall. Air leaks can cause equipment problems, damage thestructure and product, increase load, increase operating cost, and can cause a safety hazard.Eliminate all air leaks. See Table 11 for recommended line support spacing.

In low temperature application, or where proper oilcirculation cannot be maintained, an oil separatormay be required. When operating at evaporator temperatures of -20°F and lower, oil separatorsshould be considered in order to minimize theamount of oil in circulation.

In addition to the critical nature of oil return, there isno better invitation to system difficulties than anexcessive refrigerant charge. A reasonable pressuredrop is far more preferable than oversized lines whichcan contain refrigerant far in excess of the systemsneeds. On systems with a larger refrigerant charge,or on systems where liquid floodback is likely to occur, a suction line accumulator is strongly recommended.

LEAK TESTING

After all refrigerant connections are made, have beenvisually inspected and secured, add proper systemrefrigerant until the pressure is 25 to 35 PSI. Thenpressurize with dry nitrogen up to 120 to 140 PSI.Always use a pressure reducing regulator. Wait 20 to30 minutes for the refrigerant to reach all parts of thesystem. Using an electronic leak detector, check allconnections and components, both factory and fieldinstalled. The compressor, evaporator coil, and condenser coil must be checked. Valves and controls must be checked. Repair any leaks foundand re-check until no leaks are located and the pressure holds steady. Leave the system

pressurized overnight to verify that the pressureremains unchanged.

Unlocated leaks can mean unprofitable call back,additional refrigerant cost, higher energy cost, andpossible internal contamination and failure of the system. With highly hygroscopic polyol ester (POE)lubricants, leak detection is essential to preventmoisture from entering a system. The system installation must be leak free!

After leak testing has been completed, the systemmust be thoroughly evacuated before charging.

7

Page 8: Witt Sys Iom

DOUBLE RISERWHEN REQUIRED

LOOP TO PREVENTLIQUID DRAININGINTO COMPRESSOR

SLOPE

EVAPORATORS ABOVECOMPRESSOR

DOUBLE RISERWHEN REQUIRED

EVAPORATORS BELOWCOMPRESSOR

EVAPORATOR ABOVECOMPRESSOR

EVAPORATOR BELOWCOMPRESSOR

SMALLER

DOUBLE RISERDOUBLE TRAP

15' MAX

ADDTRAP

SLOPE

RISER

SLOPE

LARGERRISER

SLOPE

SLOPE

EVAPORATORS ABOVECOMPRESSOR

SLOPE

SUCTION LINE DESIGN

8

Page 9: Witt Sys Iom
Page 10: Witt Sys Iom

RECOMMENDED LINE SIZES - R-22Table 6

SYSTEM +45°F SUCTION +35°F SUCTION +25°F SUCTION +15°F SUCTION

BTUH 30' 60' 100' 150' 30' 60' 100' 150' 30' 60' 100' 150' 30' 60' 100' 150'

3000 3/8 3/8 1/2 1/2 3/8 1/2 1/2 1/2 3/8 1/2 1/2 5/8 1/2 1/2 1/2 5/8

4000 3/8 1/2 1/2 1/2 1/2 1/2 1/2 5/8 1/2 1/2 5/8 5/8 1/2 1/2 5/8 5/8

6000 1/2 1/2 1/2 5/8 1/2 1/2 5/8 5/8 1/2 1/2 5/8 5/8 1/2 5/8 5/8 5/8

9000 5/8 5/8 5/8 7/8 5/8 5/8 5/8 7/8 5/8 5/8 5/8 7/8 5/8 5/8 7/8 7/8

12000 5/8 5/8 5/8 7/8 5/8 5/8 7/8 7/8 5/8 7/8 7/8 7/8 5/8 7/8 7/8 7/8

15000 5/8 7/8 7/8 7/8 5/8 7/8 7/8 7/8 7/8 7/8 7/8 7/8 7/8 7/8 7/8 1 1/8

18000 7/8 7/8 7/8 7/8 7/8 7/8 7/8 7/8 7/8 7/8 7/8 7/8 7/8 7/8 7/8 1 1/8

24000 7/8 7/8 7/8 1 1/8 7/8 7/8 7/8 1 1/8 7/8 7/8 7/8 1 1/8 7/8 1 1/8 1 1/8 1 1/8

30000 7/8 7/8 1 1/8 1 1/8 7/8 7/8 1 1/8 1 1/8 7/8 7/8 1 1/8 1 1/8 7/8 1 1/8 1 1/8 1 1/8

36000 7/8 1 1/8 1 1/8 1 1/8 1 1/8 1 1/8 1 1/8 1 1/8 1 1/8 1 1/8 1 1/8 1 1/8 1 1/8 1 1/8 1 1/8 1 3/8

42000 7/8 1 1/8 1 1/8 1 1/8 1 1/8 1 1/8 1 1/8 1 3/8 1 1/8 1 1/8 1 1/8 1 3/8 1 1/8 1 1/8 1 3/8 1 3/8

48000 1 1/8 1 1/8 1 1/8 1 1/8 1 1/8 1 1/8 1 1/8 1 3/8 1 1/8 1 1/8 1 1/8 1 3/8 1 1/8 1 1/8 1 3/8 1 3/8

60000 1 1/8 1 1/8 1 1/8 1 3/8 1 1/8 1 1/8 1 3/8 1 3/8 1 1/8 1 1/8 1 3/8 1 3/8 1 1/8 1 3/8 1 3/8 1 5/8

75000 1 1/8 1 1/8 1 3/8 1 3/8 1 1/8 1 3/8 1 3/8 1 3/8 1 1/8 1 3/8 1 3/8 1 5/8 1 3/8 1 3/8 1 5/8 1 5/8

90000 1 3/8 1 3/8 1 3/8 1 3/8 1 3/8 1 3/8 1 3/8 1 5/8 1 3/8 1 3/8 1 5/8 1 5/8 1 3/8 1 5/8 1 5/8 1 5/8

120000 1 3/8 1 3/8 1 5/8 1 5/8 1 3/8 1 3/8 1 5/8 1 5/8 1 3/8 1 5/8 1 5/8 2 1/8 1 5/8 1 5/8 2 1/8 2 1/8

150000 1 3/8 1 5/8 1 5/8 1 5/8 1 3/8 1 5/8 1 5/8 2 1/8 1 5/8 1 5/8 2 1/8 2 1/8 1 5/8 1 5/8 2 1/8 2 1/8

180000 1 5/8 1 5/8 2 1/8 2 1/8 1 5/8 1 5/8 2 1/8 2 1/8 1 5/8 2 1/8 2 1/8 2 1/8 1 5/8 2 1/8 2 1/8 2 5/8

210000 1 5/8 1 5/8 2 1/8 2 1/8 1 5/8 2 1/8 2 1/8 2 1/8 2 1/8 2 1/8 2 1/8 2 1/8 2 1/8 2 1/8 2 1/8 2 5/8

240000 1 5/8 2 1/8 2 1/8 2 1/8 1 5/8 2 1/8 2 1/8 2 5/8 2 1/8 2 1/8 2 5/8 2 5/8 2 1/8 2 1/8 2 5/8 2 5/8

300000 2 1/8 2 1/8 2 1/8 2 5/8 2 1/8 2 1/8 2 5/8 2 5/8 2 1/8 2 1/8 2 5/8 2 5/8 2 1/8 2 1/8 2 5/8 2 5/8

360000 2 1/8 2 1/8 2 5/8 2 5/8 2 1/8 2 1/8 2 5/8 2 5/8 2 1/8 2 5/8 2 5/8 2 5/8 2 1/8 2 5/8 2 5/8 3 1/8

480000 2 1/8 2 5/8 2 5/8 2 5/8 2 1/8 2 5/8 2 5/8 2 5/8 2 5/8 2 5/8 2 5/8 3 1/8 2 5/8 2 5/8 3 1/8 3 1/8

600000 2 5/8 2 5/8 2 5/8 3 1/8 2 5/8 2 5/8 3 1/8 3 1/8 2 5/8 3 1/8 3 1/8 3 5/8 2 5/8 3 1/8 3 1/8 3 5/8

All Line Sizes are for O.D. Type L, ACR, or RS copper tube. All Lengths are "Equivalent Feet."

Shading indicates Maximum Suction Riser Size. Diameter of riser must not be larger than horizontal run.

Consider double suction risers if capacity control can reduce capacity 35% or more below design.

All line sizes selected for 2°F equivalent pressure loss maximum.

Suction traps must be used for proper oil return.

10

Page 11: Witt Sys Iom

RECOMMENDED LINE SIZES - R-22Table 7

+5°F SUCTION -10°F SUCTION -20°F SUCTION LIQUID LINE SYSTEM

30' 60' 100' 150' 30' 60' 100' 150' 30' 60' 100' 150' 30' 60' 100' 150' BTUH

1/2 1/2 5/8 5/8 1/2 1/2 5/8 5/8 1/2 5/8 5/8 5/8 1/4 1/4 1/4 3/8 3000

1/2 1/2 5/8 5/8 1/2 5/8 5/8 5/8 5/8 5/8 5/8 7/8 1/4 1/4 1/4 3/8 4000

5/8 5/8 5/8 7/8 5/8 5/8 7/8 7/8 5/8 7/8 7/8 7/8 1/4 1/4 3/8 3/8 6000

5/8 7/8 7/8 7/8 7/8 7/8 7/8 7/8 7/8 7/8 7/8 1 1/8 1/4 3/8 3/8 3/8 9000

5/8 7/8 7/8 7/8 7/8 7/8 7/8 1 1/8 7/8 7/8 1 1/8 1 1/8 3/8 3/8 3/8 3/8 12000

7/8 7/8 7/8 1 1/8 7/8 7/8 1 1/8 1 1/8 7/8 1 1/8 1 1/8 1 1/8 3/8 3/8 3/8 3/8 15000

7/8 7/8 1 1/8 1 1/8 7/8 1 1/8 1 1/8 1 1/8 1 1/8 1 1/8 1 1/8 1 1/8 3/8 3/8 3/8 3/8 18000

7/8 1 1/8 1 1/8 1 1/8 7/8 1 1/8 1 1/8 1 3/8 1 1/8 1 1/8 1 3/8 1 3/8 3/8 3/8 3/8 1/2 24000

7/8 1 1/8 1 1/8 1 3/8 1 1/8 1 1/8 1 3/8 1 3/8 1 1/8 1 3/8 1 3/8 1 3/8 3/8 3/8 1/2 1/2 30000

1 1/8 1 1/8 1 3/8 1 3/8 1 1/8 1 1/8 1 3/8 1 3/8 1 1/8 1 3/8 1 3/8 1 5/8 3/8 1/2 1/2 1/2 36000

1 1/8 1 1/8 1 3/8 1 3/8 1 1/8 1 3/8 1 3/8 1 5/8 1 3/8 1 3/8 1 5/8 1 5/8 3/8 1/2 1/2 1/2 42000

1 1/8 1 3/8 1 3/8 1 3/8 1 1/8 1 3/8 1 3/8 1 5/8 1 3/8 1 5/8 1 5/8 1 5/8 1/2 1/2 1/2 5/8 48000

1 1/8 1 3/8 1 5/8 1 5/8 1 3/8 1 3/8 1 5/8 1 5/8 1 3/8 1 5/8 1 5/8 2 1/8 1/2 1/2 5/8 5/8 60000

1 3/8 1 3/8 1 5/8 1 5/8 1 3/8 1 5/8 1 5/8 2 1/8 1 5/8 1 5/8 2 1/8 2 1/8 1/2 1/2 5/8 5/8 75000

1 3/8 1 5/8 2 1/8 2 1/8 1 3/8 1 5/8 2 1/8 2 1/8 1 5/8 2 1/8 2 1/8 2 1/8 1/2 5/8 7/8 7/8 90000

1 5/8 1 5/8 2 1/8 2 1/8 1 5/8 2 1/8 2 1/8 2 1/8 2 1/8 2 1/8 2 1/8 2 5/8 5/8 5/8 7/8 7/8 120000

1 5/8 2 1/8 2 1/8 2 1/8 1 5/8 2 1/8 2 1/8 2 5/8 2 1/8 2 1/8 2 5/8 2 5/8 5/8 7/8 7/8 7/8 150000

1 5/8 2 1/8 2 1/8 2 5/8 2 1/8 2 1/8 2 5/8 2 5/8 2 1/8 2 5/8 2 5/8 2 5/8 7/8 7/8 7/8 7/8 180000

2 1/8 2 1/8 2 5/8 2 5/8 2 1/8 2 5/8 2 5/8 2 5/8 2 1/8 2 5/8 2 5/8 3 1/8 7/8 7/8 7/8 1 1/8 210000

2 1/8 2 1/8 2 5/8 2 5/8 2 1/8 2 5/8 2 5/8 2 5/8 2 1/8 2 5/8 2 5/8 3 1/8 7/8 7/8 1 1/8 1 1/8 240000

2 1/8 2 5/8 2 5/8 3 1/8 2 1/8 2 5/8 2 5/8 3 1/8 2 5/8 3 1/8 3 1/8 3 1/8 7/8 1 1/8 1 1/8 1 1/8 300000

2 1/8 2 5/8 3 1/8 3 1/8 2 1/8 2 5/8 3 1/8 3 1/8 2 5/8 3 1/8 3 1/8 3 5/8 1 1/8 1 1/8 1 1/8 1 1/8 360000

2 5/8 2 5/8 3 1/8 3 5/8 2 5/8 3 1/8 3 1/8 3 5/8 3 1/8 3 5/8 3 5/8 3 5/8 1 1/8 1 1/8 1 1/8 1 3/8 480000

2 5/8 3 1/8 3 5/8 3 5/8 3 1/8 3 1/8 3 5/8 3 5/8 3 1/8 3 5/8 3 5/8 4 1/8 1 1/8 1 1/8 1 3/8 1 3/8 600000

Table 8

10' 15' 20' 25' 30' 40'

2° 3° 4° 4° 5° 7°

2° 2° 3° 3° 4° 5°

11

R - 22

R - 404A or R - 507

MINIMUM LIQUID SUBCOOLING (°F)TO OFFSET PRESSURE LOSS IN RISERS

RISE IN FEETREFRIGERANT

Page 12: Witt Sys Iom

RECOMMENDED LINE SIZES - R-404A, R-507Table 9

SYSTEM +30°F SUCTION +20°F SUCTION +10°F SUCTION -10°F SUCTION

BTUH 30' 60' 100' 150' 30' 60' 100' 150' 30' 60' 100' 150' 30' 60' 100' 150'

3000 3/8 3/8 1/2 1/2 3/8 1/2 1/2 1/2 1/2 1/2 1/2 5/8 1/2 5/8 5/8 5/8

4000 3/8 1/2 1/2 1/2 1/2 1/2 1/2 5/8 1/2 1/2 5/8 5/8 1/2 5/8 5/8 7/8

6000 1/2 1/2 5/8 5/8 1/2 5/8 5/8 7/8 1/2 5/8 5/8 7/8 5/8 5/8 7/8 7/8

9000 1/2 5/8 7/8 7/8 5/8 7/8 7/8 7/8 5/8 7/8 7/8 7/8 7/8 7/8 7/8 7/8

12000 1/2 5/8 7/8 7/8 5/8 7/8 7/8 7/8 5/8 7/8 7/8 7/8 7/8 7/8 7/8 1 1/8

15000 5/8 5/8 7/8 7/8 5/8 7/8 7/8 7/8 7/8 7/8 7/8 1 1/8 7/8 7/8 1 1/8 1 1/8

18000 5/8 7/8 7/8 7/8 7/8 7/8 7/8 1 1/8 7/8 7/8 1 1/8 1 1/8 7/8 7/8 1 1/8 1 1/8

24000 5/8 7/8 7/8 7/8 7/8 7/8 1 1/8 1 1/8 7/8 1 1/8 1 1/8 1 1/8 1 1/8 1 1/8 1 1/8 1 3/8

30000 7/8 7/8 7/8 1 1/8 7/8 1 1/8 1 1/8 1 1/8 1 1/8 1 1/8 1 1/8 1 3/8 1 1/8 1 1/8 1 3/8 1 3/8

36000 7/8 7/8 1 1/8 1 1/8 7/8 1 1/8 1 1/8 1 3/8 1 1/8 1 1/8 1 3/8 1 3/8 1 1/8 1 1/8 1 3/8 1 3/8

42000 7/8 1 1/8 1 1/8 1 3/8 1 1/8 1 1/8 1 3/8 1 3/8 1 1/8 1 3/8 1 3/8 1 3/8 1 3/8 1 3/8 1 3/8 1 5/8

48000 7/8 1 1/8 1 3/8 1 3/8 1 1/8 1 3/8 1 3/8 1 3/8 1 1/8 1 3/8 1 3/8 1 5/8 1 3/8 1 3/8 1 3/8 1 5/8

60000 1 1/8 1 1/8 1 3/8 1 3/8 1 1/8 1 3/8 1 3/8 1 5/8 1 1/8 1 3/8 1 5/8 1 5/8 1 3/8 1 5/8 1 5/8 1 5/8

75000 1 1/8 1 3/8 1 3/8 1 3/8 1 1/8 1 3/8 1 5/8 1 5/8 1 3/8 1 3/8 1 5/8 1 5/8 1 5/8 1 5/8 1 5/8 2 1/8

90000 1 1/8 1 3/8 1 3/8 1 5/8 1 3/8 1 5/8 1 5/8 1 5/8 1 3/8 1 5/8 1 5/8 2 1/8 1 5/8 1 5/8 2 1/8 2 1/8

120000 1 3/8 1 5/8 1 5/8 1 5/8 1 5/8 1 5/8 2 1/8 2 1/8 1 5/8 2 1/8 2 1/8 2 1/8 2 1/8 2 1/8 2 1/8 2 5/8

150000 1 5/8 1 5/8 1 5/8 2 1/8 1 5/8 2 1/8 2 1/8 2 1/8 1 5/8 2 1/8 2 1/8 2 1/8 2 1/8 2 1/8 2 5/8 2 5/8

180000 1 5/8 1 5/8 2 1/8 2 1/8 1 5/8 2 1/8 2 1/8 2 1/8 2 1/8 2 1/8 2 1/8 2 5/8 2 1/8 2 5/8 2 5/8 2 5/8

210000 1 5/8 2 1/8 2 1/8 2 1/8 2 1/8 2 1/8 2 1/8 2 5/8 2 1/8 2 1/8 2 5/8 2 5/8 2 1/8 2 5/8 2 5/8 3 1/8

240000 2 1/8 2 1/8 2 1/8 2 1/8 2 1/8 2 1/8 2 1/8 2 5/8 2 1/8 2 5/8 2 5/8 2 5/8 2 5/8 2 5/8 2 5/8 3 1/8

300000 2 1/8 2 1/8 2 5/8 2 5/8 2 1/8 2 5/8 2 5/8 2 5/8 2 1/8 2 5/8 2 5/8 3 1/8 2 5/8 2 5/8 3 1/8 3 1/8

360000 2 1/8 2 1/8 2 5/8 2 5/8 2 1/8 2 5/8 2 5/8 3 1/8 2 5/8 2 5/8 2 5/8 3 1/8 2 5/8 3 1/8 3 1/8 3 5/8

480000 2 5/8 2 5/8 2 5/8 2 5/8 2 5/8 2 5/8 3 1/8 3 1/8 2 5/8 2 5/8 3 1/8 3 5/8 3 1/8 3 1/8 3 5/8 3 5/8

600000 2 5/8 2 5/8 2 5/8 3 1/8 2 5/8 2 5/8 3 1/8 3 1/8 2 5/8 3 1/8 3 1/8 3 5/8 3 1/8 3 5/8 3 5/8 4 1/8

All Line Sizes are for O.D. Type L, ACR, or RS copper tube. All Lengths are "Equivalent Feet."

Shading indicates Maximum Suction Riser Size. Diameter of riser must not be larger than horizontal run.

Consider double suction risers if capacity control can reduce capacity 35% or more below design.

All line sizes selected for 2°F equivalent pressure loss maximum.

Suction traps must be used for proper oil return.

12

Page 13: Witt Sys Iom

RECOMMENDED LINE SIZES - R-404A, R-507Table 10

-20°F SUCTION -30°F SUCTION -40°F SUCTION LIQUID LINE SYSTEM

30' 60' 100' 150' 30' 60' 100' 150' 30' 60' 100' 150' 30' 60' 100' 150' BTUH

1/2 5/8 5/8 5/8 1/2 5/8 5/8 7/8 5/8 5/8 7/8 7/8 1/4 1/4 1/4 1/4 3000

1/2 5/8 5/8 5/8 5/8 5/8 7/8 7/8 5/8 5/8 7/8 7/8 1/4 1/4 1/4 1/4 4000

5/8 7/8 7/8 7/8 5/8 7/8 7/8 7/8 7/8 7/8 1 1/8 1 1/8 1/4 1/4 1/4 3/8 6000

5/8 7/8 7/8 1 1/8 7/8 7/8 7/8 1 1/8 7/8 7/8 1 1/8 1 1/8 1/4 3/8 3/8 3/8 9000

7/8 7/8 1 1/8 1 1/8 7/8 7/8 1 1/8 1 1/8 1 1/8 1 1/8 1 3/8 1 3/8 3/8 3/8 3/8 3/8 12000

7/8 1 1/8 1 1/8 1 1/8 7/8 1 1/8 1 1/8 1 1/8 1 1/8 1 1/8 1 3/8 1 3/8 3/8 3/8 3/8 1/2 15000

7/8 1 1/8 1 1/8 1 3/8 7/8 1 1/8 1 1/8 1 3/8 1 1/8 1 1/8 1 3/8 1 3/8 3/8 3/8 1/2 1/2 18000

1 1/8 1 1/8 1 1/8 1 3/8 1 1/8 1 1/8 1 3/8 1 3/8 1 1/8 1 3/8 1 5/8 1 5/8 3/8 1/2 1/2 1/2 24000

1 1/8 1 1/8 1 3/8 1 3/8 1 1/8 1 1/8 1 3/8 1 3/8 1 1/8 1 3/8 1 5/8 1 5/8 1/2 1/2 1/2 5/8 30000

1 1/8 1 3/8 1 3/8 1 5/8 1 3/8 1 3/8 1 3/8 1 5/8 1 3/8 1 3/8 1 5/8 1 5/8 1/2 1/2 1/2 5/8 36000

1 1/8 1 3/8 1 3/8 1 5/8 1 3/8 1 3/8 1 5/8 1 5/8 1 3/8 1 3/8 1 5/8 1 5/8 1/2 1/2 5/8 5/8 42000

1 3/8 1 3/8 1 5/8 1 5/8 1 3/8 1 3/8 1 5/8 1 5/8 1 3/8 1 3/8 1 5/8 1 5/8 1/2 1/2 5/8 5/8 48000

1 3/8 1 5/8 1 5/8 1 5/8 1 3/8 1 5/8 1 5/8 1 5/8 1 5/8 1 5/8 2 1/8 2 1/8 1/2 5/8 5/8 5/8 60000

1 5/8 1 5/8 2 1/8 2 1/8 1 5/8 1 5/8 2 1/8 2 1/8 2 1/8 2 1/8 2 1/8 2 5/8 5/8 5/8 5/8 7/8 75000

1 5/8 2 1/8 2 1/8 2 1/8 1 5/8 2 1/8 2 1/8 2 1/8 2 1/8 2 1/8 2 5/8 2 5/8 5/8 5/8 7/8 7/8 90000

2 1/8 2 1/8 2 1/8 2 5/8 2 1/8 2 1/8 2 1/8 2 5/8 2 1/8 2 5/8 2 5/8 3 1/8 5/8 7/8 7/8 7/8 120000

2 1/8 2 1/8 2 5/8 2 5/8 2 1/8 2 1/8 2 5/8 2 5/8 2 5/8 2 5/8 3 1/8 3 1/8 7/8 7/8 7/8 7/8 150000

2 1/8 2 5/8 2 5/8 2 5/8 2 1/8 2 5/8 2 5/8 2 5/8 2 5/8 2 5/8 3 1/8 3 5/8 7/8 7/8 1 1/8 1 1/8 180000

2 1/8 2 5/8 2 5/8 3 1/8 2 5/8 2 5/8 2 5/8 3 1/8 2 5/8 3 1/8 3 1/8 3 5/8 7/8 1 1/8 1 1/8 1 1/8 210000

2 5/8 2 5/8 2 5/8 3 1/8 2 5/8 2 5/8 3 1/8 3 1/8 3 1/8 3 1/8 3 5/8 3 5/8 7/8 1 1/8 1 1/8 1 1/8 240000

2 5/8 2 5/8 3 1/8 3 5/8 2 5/8 3 1/8 3 1/8 3 5/8 3 1/8 3 1/8 3 5/8 4 1/8 1 1/8 1 1/8 1 1/8 1 3/8 300000

2 5/8 3 1/8 3 5/8 3 5/8 3 1/8 3 1/8 3 5/8 3 5/8 3 1/8 3 5/8 4 1/8 5 1/8 1 1/8 1 1/8 1 1/8 1 3/8 360000

3 1/8 3 5/8 3 5/8 4 1/8 3 5/8 3 5/8 4 1/8 4 1/8 3 5/8 4 1/8 5 1/8 5 1/8 1 1/8 1 1/8 1 3/8 1 3/8 480000

3 1/8 3 5/8 4 1/8 4 1/8 3 5/8 4 1/8 4 1/8 5 1/8 4 1/8 4 1/8 5 1/8 5 1/8 1 1/8 1 3/8 1 3/8 1 5/8 600000

Table 11

Support all lines securely using cushioned clamps.

Clamps should be a minimum of 12 inches from elbows.

13

MAXIMUM DISTANCE BETWEENTYPE "L" COPPER TUBE LINE SUPPORTS

3/8 - 1/25/8 - 7/8

1 1/8 - 2 1/82 5/8 - 5 1/8

TUBE O.D. (INCHES) MAXIMUM FEET46810

Page 14: Witt Sys Iom

All field wiring must be in compliance with local and System wiring diagrams are located inside the condensingnational codes. Use only copper conductors of the unit control panel door. Wire components as shown on theappropriate size. The equipment specplates are marked wiring diagrams. All equipment must be grounded. To aidwith the electrical characteristics. All field wiring should the evacuation and provide additional compressor protectionenter the equipment control panels through bushings. during charging and start-up, the crankcase heater should

be energized 24 hours before charging begins. After start-Disconnect switches and evaporator branch circuit up, any vibrating armored cable should be secured and protection are supplied by the installer and must comply must not contact refrigerant tubing.with the governing electrical codes.

The room thermostat and liquid line solenoid should beBe sure the power is disconnected and tighten all wired in series per the diagrams. The pumpdown cycle isconnections before starting equipment. If any electrical mandatory to maintain compressor warranty. Carefullycomponents are located outdoors, use the appropriate follow the diagrams of multiple evaporator systems tooutdoor fixture, fittings, and conduit. ensure proper defrosting of all units.

208/230/3 or 460/3 POWER SUPPLY FAN MOTOR POWER

FROM FIELD SUPPLIED DISCONNECT 120 or 208/230 VOLTS

O O

O O O O O LLS

O O O EVAP ROOM T'STAT

CIRCUIT BREAKER FANSor TERMINAL BLOCK

TB1 ALL UNITS MUST BE GROUNDED

44 38 2 (N) Volts & phase toO O O match evap fans For factory wiring refer to the diagram in the unit.

O O O O O If liquid line solenoid (LLS) is factory mounted orLLS EVAP if unit has low ambient flooded condenser option,

ROOM T'STAT FANS connection to TB1 - 38 terminal must be made.

208/230/ POWER SUPPLY 208/230 or 460 POWER SUPPLY

FROM FIELD SUPPLIED DISCONNECT FROM FIELD SUPPLIED DISCONNECT

O O O O O OO O O O O OCIRCUIT BREAKER CIRCUIT BREAKER

or TERMINAL BLOCK or TERMINAL BLOCK

TB1 TB2 TB1 TB2

44 38 2 N X 4 3 44 38 2 N X 4 3

O O O O O O O O O O O O O O

O O O O

LLS LLS

ROOM T'STAT O O O O TB - Terminal Block ROOM T'STAT O O O O

N X 4 3 LLS - Liquid Line Solenoid N X 4 3

EVAP EVAP

OFF-CYCLE AIR DEFROSTWITH OR WITHOUT TIMER

ALTERNATE UNIT COOLER WIRINGAIR DEFROST WITHOUT TIMER

14

CONDENSINGUNIT

CONDENSINGUNIT

GROUND

LUG

GROUND

LUG

FIELD WIRING

ELECTRIC DEFROST, 1Ø FANS & HEATERS HOT GAS DEFROST, 1Ø FANS

TYPICAL FIELD WIRING

GROUND

LUG

CONDENSINGUNIT

Page 15: Witt Sys Iom

208/230/3 POWER SUPPLY

FROM FIELD SUPPLIED DISCONNECT

O O OO O O ALL UNITS MUST BE GROUNDED

CIRCUIT BREAKER Provide jumper from N to 3 if

or TERMINAL BLOCK heater safety (HS) is not used. For factory wiring refer to the diagram in the unit.

TB1 TB2 C6 C7 If liquid line solenoid (LLS) is factory mounted or44 38 2 N X 4 3 if unit has low ambient flooded condenser option,O O O O O O O O O O O O O connection to TB1 - 38 terminal must be made.

O O

LLS

O O O O O O O O O O

T'STAT N X 4 3 H1 H2 H3 H1 H2 H3

TB - Terminal Block

C# - Contactor #

LLS - Liquid Line Solenoid

H - Heater terminal

208/230/3 POWER SUPPLY

FROM FIELD SUPPLIED DISCONNECT

O O OO O O ALL UNITS MUST BE GROUNDED

CIRCUIT BREAKER

or TERMINAL BLOCK For factory wiring refer to the diagram in the unit.

TB1 TB2A TB2B TB2C If liquid line solenoid (LLS) is factory mounted or44 38 2 N X 4 3 N X 4 3 N X 4 3 if unit has low ambient flooded condenser option,O O O O O O O O O O O O O O O connection to TB1 - 38 terminal must be made.

O O

LLS

O O O O O O O O O O O O

T'STAT N X 4 3 N X 4 3 N X 4 3

TB - Terminal Block

LLS - Liquid Line Solenoid

TYPICAL FIELD WIRING

GROUND

LUG

HEATER

CONDENSINGUNIT

ELECTRIC DEFROST, MULTIPLE EVAPORATOR, 1Ø FANS & HEATERS

ELECTRIC DEFROST, 1Ø FANS & 3Ø HEATERS

ROOM

EVAP

HEATER

ROOM

15

THE MOST POSITIVE AND DEPENDABLE MEANS OF KEEPING LIQUID REFRIGERANTOUT OF THE COMPRESSOR CRANKCASE IS THE USE OF A PUMPDOWN CYCLE

GROUND

LUG

EVAP A EVAP B EVAP C

CONDENSINGUNIT

Page 16: Witt Sys Iom

208/230/3 POWER SUPPLY

FROM FIELD SUPPLIED DISCONNECT

O O O CONDENSING UNITO O OCIRCUIT BREAKER Provide jumper from N to 3 if

or TERMINAL BLOCK heater safety (HS) is not used.

TB1 TB2A C6 TB2B C7 TB2C C8

44 38 2 N X 4 3 N X 4 3 N X 4 3

O O O O O O O O O O O O O O O O O O O O O O O O

O O

LLS

O O O O O O O O O O O O O O O O O O O O O

T'STAT N X 4 3 H1 H2 H3 N X 4 3 H1 H2 H3 N X 4 3 H1 H2 H3

TB - Terminal Block

C# - Contactor #

LLS - Liquid Line Solenoid ALL UNITS MUST BE GROUNDED

H - Heater terminal

208/230/3 or 460/3 POWER SUPPLY

FROM FIELD SUPPLIED DISCONNECT

O O O CONDENSING UNITO O OCIRCUIT BREAKER Provide jumper from N to 3 if

or TERMINAL BLOCK heater safety (HS) is not used.

TB1 TB2A C6 TB2B C7 TB2C C8 C5

44 38 2 N X 4 3 N X 4 3 N X 4 3

O O O O O O O O O O O O O O O O O O O O O O O O O O O

O O

LLS

ROOM O O O O O O O O O O O O O O O O O O O O O

T'STAT N X 4 3 H1 H2 H3 N X 4 3 H1 H2 H3 N X 4 3 H1 H2 H3

M1 M2 M3 M1 M2 M3 M1 M2 M3

TB - Terminal Block O O O O O O O O O

C# - Contactor #

LLS - Liquid Line Solenoid

H - Heater terminal

M - Motor terminal ALL UNITS MUST BE GROUNDED

For factory wiring refer to the diagram in the unit. If liquid line solenoid (LLS) is factory mounted or if condensing unit haslow ambient flooded condenser option, connection to TB1 - 38 terminal must be made.

HEATER

EVAP C

16

ELECTRIC DEFROST, MULTIPLE EVAPORATOR, 3Ø FANS AND HEATERS

GROUND

LUG

EVAP A EVAP B

MOTORHEATER

TYPICAL FIELD WIRING

ROOM

ELECTRIC DEFROST, MULTIPLE EVAPORATOR, 1Ø FANS AND 3Ø HEATERS

GROUND

LUG

HEATER HEATER

HEATER

EVAP CEVAP BEVAP A

HEATER

Page 17: Witt Sys Iom

17

EVACUATION

Proper installation procedures must include DEEPEVACUATION of the system. It takes both a deepvacuum and filter-drier in a system for properprotection. The filter-drier will pick up moisture, oxides,fibers, particles of metal, flux, and other materials thatevacuation cannot remove. Removing the AIR andMOISTURE from a system by applying a DEEPVACUUM is an absolute necessity.

Only by using a rotary deep vacuum pump and anelectronic deep vacuum gauge can the installer besure a system is dehydrated sufficiently to preventearly breakdown. By using a rotary deep vacuumpump and the multiple evacuation method, anelectronic deep vacuum gauge can indicate that thesystem has been adequately evacuated and if a leakexists. The installer must comply with governmentregulations and use appropriate procedures andequipment to avoid releasing refrigerants into theatmosphere.

A two-valve test manifold mounted on the vacuumpump is recommended. To shorten the evacuationtime and to prevent erroneous gauge readings, installthe largest diameter vacuum line feasible and as shortas practical. A minimum 3/8 inch OD copper tube orseamless metal hose is recommended. The larger thesystem, the larger the vacuum line diameter should be.Do not use neoprene hose for evacuation. Neoprenehose is not sufficiently vacuum tight for evacuation ortesting. Using a deep vacuum sealant on all lineconnections and fittings is good practice.

Be prepared to frequently change the vacuum pumpoil. Use oil that is specifically refined for rotary deepvacuum pumps. A vacuum pump cannot create avacuum less than the vapor pressure of its sealing oil.Clean and dry deep vacuum oil is essential for propersystem evacuation and protection of the vacuumpump. If the vacuum pump cannot quickly pull down toa low blank-off vacuum reading the oil must bechanged. If the pump and oil are in good condition itshould quickly attain a 100 micron reading whenblanked-off. We recommend checking the pumpcondition with this test before attempting to evacuate arefrigeration system.

Use an electronic deep vacuum gauge. The systemmust hold at 500 microns or less with R-22 systemsand 400 microns or less on R-404A or R-507systems after final evacuation. The vacuum gaugeshould hold very close to this reading for 10 minutesafter the pump is closed off. Holding steady at or closeto this micron reading indicates the system is dry andleak free. The compressor service valves must be

open for the final evacuation so that the compressorand entire system is evacuated.

Pull a continuous vacuum for a minimum of 4 hours.Longer is better. On systems over 5 horsepower pullthe vacuum overnight. POE lubricants are muchslower than mineral oils to release moisture. Properevacuation of systems with POE lubricants can takemore time. The vacuum decay test for 10 minutesdescribed in paragraph 5 is strongly recommended.

Deep evacuation is an absolute necessity!

Make the charging line connection with a line purged ofair and break the vacuum. Break the vacuum with theproper system refrigerant and pressurize the system to5 to 10 PSI before removing the vacuum pump lines.DO NOT START THE COMPRESSOR WHILE THESYSTEM IS UNDER VACUUM. Do not use thecompressor as a vacuum pump. Do not allow thesystem to stand at deep vacuum more than one hourwithout the vacuum pump operating.

EVACUATION RECORD

System ID __________________________ HP_____

Start Vacuum: _______ AM / PM Date ___- ___- ___

________ microns after 4 hours

________ microns after 8 hours

________ microns after 12 hours

________ microns after 16 hours

Stop Vacuum: _______ AM / PM Date ___- ___- ___

________ microns after ______ hours of evacuation

________ microns 10 minutes after pump shut off

Evacuated by ________________________________

Page 18: Witt Sys Iom

CHARGING and START-UP

The control circuit should be energized 24 hoursbefore charging and start-up to open the liquidline solenoid and turn on the crankcase heater.This will assist the evacuation and dehydrationprocess and provide additional compressor protection during the charging and start-up.

Charge refrigerant into a system through a filter-drier in the charging line. This provides furtherassurance the refrigerant charge is clean and dry.The system refrigerant capacity is approximately80% of the condenser, receiver, and liquid linecapacity. If the condenser volume or refrigerantcapacity is unknown, the system refrigerantcapacity is often calculated at 90% of the receiverand liquid line capacity. Be cautious if thecalculated charge is exceeded. Weigh the refrigerant. The actual refrigerant charge shouldbe less than the calculated capacity. DO NOTcharge liquid refrigerant into the suction sideof the compressor.

Be sure the compressor discharge valve is open.The suction valve should be open 2 or 3 turns,with a valve stem wrench attached for quick throttle adjusting. High and low pressure gaugesshould be attached. Liquid charging is faster. If R-404A or R-507 is used, liquid charging ismandatory. R-404A and R-507 refrigerant cylinders have a dip tube and liquid is chargedwith the cylinder upright. Break the final vacuumby charging liquid refrigerant into the receiveroutlet valve access or the area of liquid line downstream from the receiver outlet.

Approximately 50 to 60% of the system charge can usually be injected into the receiver areabefore it is necessary to start the compressor forthe system to accept more refrigerant . It may benecessary to throttle the compressor suctionvalve to keep suction pressures reasonable andprevent tripouts during charging and pull-down. Ifit is necessary to add liquid refrigerant to thesuction side, a full control ball valve must be usedin the charging line to slowly meter refrigerantvapor into the system.

If the condensing temperature is 105°F orgreater, charge the system until the sight glassjust clears, being careful not overcharge. If thecondensing temperature is below 105°F, a part ofthe condenser coil can be blocked to raise the condensing temperature to 105°F. Be careful not

to block the air blast against the compressor. This procedure satisfies systems with floatinghead pressure control. Follow the same procedure for systems with low-ambient floodedcondenser head pressure control.

With 105°F condensing temperature, charge untilthe sight glass just clears. Then accurately weighin the additional pounds of refrigerant specified inthe chart on page 19. There is also a charging tagon the unit. The pounds specified on the tag supercedes this IOM. This will provide adequatecharge for all ambient operation. The actualcharge should not exceed the calculated systemscapacity. After system charging and room pull-down is complete , test the ability of the system tosuccessfully pump down. Raise the roomthermostat setting to close the liquid solenoid.The system must pumpdown and shut off at the low pressure cutout setting. See Table 13.

Unblock the condenser coil and return the roomthermostat to the desired setting.

The first two to three hours of operation afterstart-up is a critical time. Do not just start-up andwalk away. Watch for floodback and adjust theexpansion valve if necessary. Observe systempressures. Check all fans on the evaporator andcondensing unit to be sure they are operationaland turning the proper direction. Record thepounds of refrigerant charged into the system.Check the compressor oil level frequently. On low temperature systems the fan delay controlmay cycle the evaporator fans. To keep the fanson until the room pulls down, it may be necessaryto jumper the fan delay control.

Check voltage and amperage at the compressor.Voltage must be within 10% of the specplate rating. Amperage should be approximately equalacross all three lines. Check the piping for vibration and add supports if needed. Check electrical conduit for vibration and route to preventcontact with tubing.

Use the Start-Up Check List on page 24 to assistyou. Don’t forget to remove the fan delay jumperif one was used. Also, fully open the suctionvalve. After the room has pulled down to designtemperature and held for 24 hours, review the system guidelines on page 23 and complete a system service record on page 25.

18

Page 19: Witt Sys Iom

POUNDS OF ADDITIONAL REFRIGERANT CHARGETO ADD FOR FLOODED HEAD PRESSURE CONTROL

Table 12Proline 1/2 - 6 HP Proline 1/2 - 6 HP WD - Series 3 - 22 HP WV - Series 20 - 80 HP

Model Lbs. to Model Lbs. to Model Lbs. to Model Lbs. toPLH Add PLS Add WDLD Add WVLD Add

H051H22 2.5 S050H22 1.3 3L22 9.5 SINGLEH050M44 2.2 S050M44 1.1 3L44 8.2 20H22 58H050L44 2.2 S050L22 1.3 4L22 14.3 20M44 50H075H22 2.5 S050L44 1.1 4L44 12.3 25H22 78H075M44 3.2 S075H22 2.5 5H22 14.3 25M44 67H075L44 3.2 S075L22 2.5 5M44 16.4 27L22 58H100H22 3.8 S075L44 3.2 5L22 14.3 27L44 50H100L44 3.2 S100H22 3.8 5L44 12.3 30H22 98H101M44 4.3 S100M44 4.3 6M44 23.0 30M44 84H150H22 5.0 S100L22 3.8 6L22 14.3 30L22 58H150M44 4.3 S100L44 3.2 6L44 12.3 30L44 50H150L44 4.3 S150H22 5.0 7H22 27.0 35H22 115H200H22 7.5 S150L44 4.3 7M44 23.0 35M44 99H201M44 8.6 S200H22 7.5 8H22 27.0 40H22 144H200L44 6.5 S200M44 6.5 8M44 23.0 40M44 124H250H22 7.5 S200L22 7.5 8L22 27.0 50H22 156H300H22 12.4 S200L44 6.5 8L44 23.0 50M44 134H300M44 10.6 S201L22 7.5 9L22 27.0 60H22 195H300L44 10.6 S202L22 7.5 9L44 23.0 60M44 168H400H22 12.4 S250L44 7.1 10H22 44.0H400M44 10.6 S300H22 8.3 10M44 38.0 PARALLELH500H22 16.5 S300M44 7.1 10L22 27.0 17H22 58H500M44 14.2 S300L22 8.3 10L44 23.0 17M44 50

PLD S300L44 7.1 12H22 44.0 21H22 78D300L22 12.4 S400H22 12.4 12M44 38.0 21M44 67D300L44 10.6 S400M22 12.4 12L22 27.0 24H22 98D400L22 12.4 S400M44 10.6 12L44 23.0 24M44 84D400L44 10.6 S500H22 16.5 15H22 54.0 31H22 86D500H22 16.5 S500M22 16.5 15M44 46.0 31M44 74D500M44 14.2 15L22 44.0 41H22 115D500L22 12.4 15L44 38.0 41M44 99D500L44 10.6 22L22 54.0 44L44 74

22L44 46.0 51H22 11751M44 10154L44 99

CHARGING STEPS - (See Page 18) 61H22 1951. Charge as necessary to achieve a clear sight glass, with the air 61M44 168 intake to the condenser blocked, to maintain a minimum 200 psi 61L44 124 head pressure. This will prevent gas from by passing through the 71H22 173 flood valve. DO NOT OVERCHARGE! Just clear the glass. 71M44 1492. Add the exact amount of refrigerant shown in this table of the 81H22 231 model being charged. This will provide the system the charge it 81H22 198 requires for all weather, flooded, operation.

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RECOMMENDED INITIALLOW PRESSURE CONTROL SETTING - PSIG

Table 13

MINIMUM R-22 R-404A, R-507

SYSTEM * MAXIMUM CUT MAXIMUM CUTTEMP. °F CUT IN OUT CUT IN OUT

50 75 25 85 3540 60 20 70 3530 45 20 55 35

20 40 15 50 3010 30 10 45 250 20 5 25 5

-10 15 1 20 1-20 10 0 12 1-30 6 8" Vac. 8 8" Vac.

*Minimum System Temperature is the coldest point in the system, whether it is the outdoor

ambient or the refrigerated room temperature. The Minimum System Temperature dictatesthe low pressure control setting. When possible, keep the low pressure cut out at positivepressure. Low pressure controls are factory set at 15 PSI cut in and 3 PSI cut out.

RECOMMENDED INITIALHIGH PRESSURE CONTROL SETTING - PSIG Table 14

R-22 R-404A, R-507CUT IN CUT OUT CUT IN CUT OUT

270 - 275 350 - 360 315 - 320 390 - 400

ESTIMATING VENTILATION REQUIREMENTSfor INDOOR AIR COOLED CONDENSING UNITS Table 15

SATURATED SUCTION °F CFM PER HORSEPOWER

High temp. +28 to +45 2000

Med. temp. +1 to +27 1500

Low temp. -1 to -30 1000These estimates are based on limiting the equipment room ventilationair temperature rise to 10°F above the make up air. The total fresh airCFM must be available to the condenser coil inlets at design ambient.The temperature rise may be reduced by increasing the CFM.

High temperature CFM required = HT HP x 2000 = ____________________

Med. temperature CFM required = MT HP x 1500 = ____________________

Low temperature CFM required = L T HP x 1000 = ____________________

TOTAL estimated CFM required = (add above) _____________________

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DEFROST

AIR DEFROST - An air defrost system, sometimescalled off-cycle, is wired so that the evaporator fansrun continuously, unless manually de-energized.Whenever the compressor stops, the room air (minimum = 34°F) warms the coil to room temperature melting the frost. It is essential that thefrost completely melts and drains each time the compressor cycles off. If it does not, a partial defrostresults, and the residual water and slush will re-freeze into ice during the next run cycle. Ice removalwill require a manual defrost.

Adequate off-cycle time is a function of systemcapacity. If the system is too small for the room, icebuild-up will usually result. Use of an air defrost timeris sometimes successful on undersized systems toavoid coil icing. A temporary rise in room temperature will occur during the defrost cycle.

Optional defrost timers are suitable for Time Initiated,and either Time or Temperature terminated airdefrost. Time termination is done by setting the fail-safe dial of the timer to the desired defrost duration. This keeps the compressor off during thatduration. Temperature termination requires themounting of a close-on-rise termination thermostatwhose remote sensing bulb can be affixed to the coilat the point of heaviest frosting. The best setting for the termination temperature is usually thedesign room temperature.

ELECTRIC DEFROST - The recommended electricdefrost circuitry is typical wiring designed for theParagon 8145-20 and Precision 6145-20 defrosttimers, with the addition of Lock-out Relay R1. Thisrelay prevents the simultaneous operation of thecompressor and the defrost heaters, and thus avoidsthe need for oversized wiring and service.

Relay R1 contact (4-5) is normally closed ( relay de-energized), and is wired in series with the defrostheaters and terminal 3 (heater power) in the timer.Whenever R1 is energized, the relay contact opens,breaking the heater power circuit. R1 holding coil isin parallel with the compressor motor on singlephase, or the compressor contactor holding coil (M1)on three phase, and is therefore energized any timethe compressor starts. When the timer switches thesystem into defrost, the heaters will not energize untilthe compressor completes pumpdown and stops,even through the timer has applied power to terminal3. If the compressor starts up for additional pumpdown during defrost, R1 energizes, breakingpower to the heaters until the compressor stops again.

TIMER SETTINGS - Timers should be set to the correct time. Determine the number of defrost perday and the best time of day to occur. Insert defrostpins accordingly. Set the fail-safe time to terminatethe defrost a few minutes beyond the estimated temperature termination time. Air defrost fail-safe(termination time) is usually 30 to 50 minutes. Thecolder the room, the longer the fail-safe time required. Electric defrost systems normally have a25 to 35 minute fail-safe time. Hot gas defrost systems usually have a 10 to 25 minute fail-safe.

SUCCESSFUL DEFROSTING - Numerous factorsshould be considered when selecting and starting uplow temperature refrigeration systems. For storagefreezers holding packaged product, two defrost perday is normal. If the freezer has heavy usage withlots of door openings then three or four defrost perday may be required. For blast chilling and freezingor freezing of products with high moisture content, sixor more defrost per day may be necessary. Do nothave more defrosts than are necessary. Unnecessaryextra defrosts add heat to the refrigerated space thatmust be removed. Excessive defrost periods mayalso cause steaming and lead to undesirable ice formation on the unit cooler, ceiling, and product.

Another factor to consider when determining the frequency of defrost is oil return. Oil will tend to settle out in the evaporator or suction line on lowtemperature systems. This oil should return to thecompressor shortly after a defrost. Watch the compressor oil level. If it becomes low, a defrostmay be needed for oil return. In critical situations anoil separator may be required. Two to four defrost per day are usually sufficient to maintain proper oillevel in the compressor. The new synthetic (POE)lubricants are considered more miscible with refrigerant than mineral oil and do not separate outas rapidly. Some installations may require only onedefrost per day.

Evaporators with a medium frost load will defrostbest. If the frost load is very light, the moisture cannot form water drops and run off the fins.Instead, it will vaporize off as steam and can createice on colder surfaces like the ceiling, fan blades, fanguards, and evaporator housing. With medium frostloads, the frost will melt off as water and drain away.Too heavy a frost load will restrict air flow and causeuneven temperature in the freezer. Defrost with amedium frost load to maintain stable room temperature, optimum evaporator performance, andhave a complete clearing of all frost.

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Once ice forms in an evaporator coil it keeps buildingmore ice and eventually will lead to equipment failureif not manually defrosted. Some symptoms of iceforming in the coil are: (1) Loss of air circulation andair throw, (2) Loss of room temperature, (3) No off-cycle time, (4) Floodback, and (5) Water spitting outof the fans or coil on air defrost systems. Long termice formation will crush the refrigerant tubes in the

coil causing leaks and major equipment problems.If ice formation is suspected, carefully check the interior rows of the coil with a good light. Ice formation usually starts at the bottom of the coil inthe middle rows and can be difficult to detect. Anyice formation, however small, requires a manuallyassisted defrost. Clear 100% of the ice before placing a unit back into operation.

DEFROST (continued)

Always allow space for good air throw, air circulation,air return, cleaning and servicing of the evaporatorunit. Always leave air circulation space between theproducts and walls of the cooler. Leave space between the boxes or cartons of product for thefastest temperature reduction or freezing. The largerthe mass of product, the longer it takes to removeheat from the center of that mass. Divide the masswith air circulation space so the circulating cold aircan carry the heat away from the product faster.Baffles may be required to direct air to specific areasof a room. How the product is stacked will influencepulldown time and stable product temperature.Direct the air to flow over and through the product.Refer to the evaporator location recommendations onpage 4 to 5. It is a good practice to avoid stackingproduct closer than 12 inches to the evaporator drainpan. The room size, layout, aisleways, heigh, doorlocation, product stacking, and other factors influencethe location of the evaporator. Locate evaporatorsso that the air pattern covers the entire room. Avoid

placing evaporators above or close to doors. Directthe air stream toward the door or down an aislewhen possible. Use strip curtains on doors if theyare open frequently or for extended periods.Minimize the entry of warm, humid, air into the room.

There are always exceptions to the guidelines forgeneral use storage cooler or freezers. Specialexceptions could be the product, air velocity, temperature, humidity, process, people, or machineryinvolved. Tomatoes, bananas, flowers, meat cuttingand processing, and many other products have special requirements. Work or process rooms withpeople involved may have specifications requiringspecial attention. Facilities with USDA or otherinspections can have special regulations and we suggest contacting the local inspector when selectingand locating equipment. Blast chill or blast freezerooms may require special equipment or parts. Wehave years of experience and are always ready toassist you with special applications or projects.

PRODUCT LOADING and AIR CIRCULATION

Evap. AirAir

Air

Air

Product

Air

Air

Door

Product

Pallets-Air

TYPICAL EVAPORATOR LOCATION IN A FREEZERDrawing 9

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EVAPORATOR SUPERHEAT

Normally 6° to 12° is acceptable on most refrigerationsystems. Preferably 6° to 8° on low temperature systems and 8° to 10° on medium temperature systems. Obtain evaporator superheat by measuringthe suction line temperature at the expansion valvebulb. Obtain pressure at a Schrader fitting in the evaporator suction connection area, near the expansionvalve bulb, and convert to temperature with a

pressure-temperature chart. Subtract the convertedtemperature from the measured temperature and thedifference is superheat at the evaporator. Obtain thedesired superheat by adjusting the expansion valve.Evaporator superheat greater than 14°F can substantially reduce the evaporator and systemcapacity, while superheat less than 4°F has thepotential for floodback.

COMPRESSOR SUPERHEAT

To improve compressor life expectancy 25° to 40° ofcompressor superheat is preferred. Copeland recommends a MINIMUM of 20°F superheat at thecompressor. Compressor superheat is sometimescalled suction superheat. Obtain compressor super-heat by measuring the suction line temperature about 6to 12 inches from the compressor service valve.Obtain pressure at the suction service valve and convert to temperature with a pressure-temperaturechart. Subtract the converted temperature from themeasured temperature and the difference is superheatat the compressor. Compressor superheat is a criticalvalue and should override evaporator superheat. Toolow a compressor superheat can permit liquid return tothe compressor causing damage or failure. Too high a

compressor superheat can cause high dischargetemperature, resulting in lubricant breakdown, compressor overheating and can lead to compressordamage or failure. System capacity decreases ascompressor superheat increases so superheat shouldbe as low as practical, but with 20°F MINIMUM at alltimes. Compressor superheat can be changed byadjusting the expansion valve, adding a suction-liquidline heat exchanger, or by insulating just the suctionline. Remember that increasing the superheat at theevaporator will decrease the evaporator capacity.For that reason, suction-liquid line heat exchangerare often used on systems with short line runs. Eachsystem must be thoughtfully planned and adjusted toobtain optimum performance.

RETURN GAS TEMPERATURE

Although compressors may be capacity rated with 65°Freturn gas, most low temperature systems should notbe operated at that condition. A 65°F return gas is usually acceptable on medium temperature systems.We recommend a 20°F to 40°F maximum return gastemperature on low temperature systems. Higherreturn gas temperatures on low temperature systems

may cause compressor overheating and shortencompressor life. Always maintain a minimum 20°Fsuperheat at the compressor.

If necessary, insulate the suction line on low temperature systems to improve the return gastemperature and superheat at the compressor.

DISCHARGE LINE TEMPERATURE

The discharge line temperature should be measuredabout 6 inches down line from the compressor discharge service valve. Discharge line temperaturehas a direct reationship to internal temperatures in thecompressor. A discharge line temperature of 220°F orlower is desirable and will improve compressor lifeexpectancy. Maintaining a discharge line temperaturebelow 220°F prevents oil breakdown, prevents excesswear on internal parts, and is assurance that the compressor is not overheating. Copeland recommendsa MAXIMUM discharge line temperature of 225°F.“Lower is better.”

There is a relationship between discharge line temperature and return gas temperature. Lowering thereturn gas temperature by insulating the suction line

will usually lower the discharge line temperature aboutthe same degree.

Make sure low temperature compressor have a directair blast over the compressor body. This air blast isessential to maintain proper cooling of low temperaturecompressors. Check head cooling fans for operation.

An operational check and adjustment is recommendedafter the room has pulled down to operating temperature and the outdoor ambient is above 70°F.To simulate design conditions, the condenser face canbe partially blocked (Do not block condenser air blastcooling compressor body) to raise the head pressure.Carefully adjust each system for optimum performanceand trouble free long life.

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SYSTEM START-UP CHECK LIST

Customer_________________________________ Job Name___________________________

City/State____________________________ System No.___________________ Date_________________

Condensing Unit Model No.__________________________________ Serial No._______________________

Evaporator Model No._____________________________ Qty.______ Serial No._______________________

Room No. or Name__________________ Design Temp.________°F Size(Ft.)______L x ______W x_____H

Suction Line_______OD Liquid Line_______OD Equivalent Length_______Ft. Liquid Lift_______Ft.

Leak Test at________PSIG, for_____Hours System is Leak Free_______

Evacuated____Times to______Microns + Final Vacuum to_________Microns, for_____Hours Total Hrs____

Sight Glass Dry______ Pressure Controls Set______ Thermostats Set______ Outdoor Ambient_________°F

Design Voltage____________ Test Volts___________ Control Circuit Volts___________

Disconnect Fuse Size______Amps Control Circuit Fuse______Amps Estimated Refrigerant Charge_____Lbs.

Refrigerant R-________ Charge______ + ______ + ______=_________Total Lbs. Sight Glass Clear______

Compressor Oil Level______Glass Evap. Fans Running_______ Room Temp at Start-up_________°F

Room Temp at 1 Hr.______°F Compressor Oil Level______Glass Defrost Timer Set_________

Room Temp at 2 Hr.______°F Compressor Oil Level______Glass Sight Glass Clear______

Room Temp at 4 Hr.______°F Compressor Oil Level______Glass Outdoor Ambient________°F

Electrical Specplate Test Amps

Component Amps L1 L2 L3

Compressor __________ _________ _________ _________

Condenser __________ _________ _________ _________

Evaporator __________ _________ _________ _________

Defrost Heaters __________ _________ _________ _________

Evaporator Suction Temp_______°F Evaporator Suction Pressure________PSIG

Convert PSIG to________°F Evaporator Superheat________°F

Compressor Suction Temp________°F Compressor Suction Pressure________PSIG

Convert PSIG to________°F Compressor Superheat________°F Sight Glass Clear________

Compressor Discharge Pressure________PSIG Compressor Discharge Line Temp_______°F

Liquid Temp Leaving Condensing Unit________°F Liquid Temp Entering Expansion Valve________°F

Evaporator Drain Line Trapped________, Heated________, Sloped________, Will not freeze up________

Type of Defrost: _____Air _____Electric _____Hot Gas Defrost Time______Min. Is Coil Clean?______

Temperature Termination________ Fan Delay________ Is Defrost Satisfactory?________

Compressor Oil Level________Glass Timer Set________Defrost per Day with________Minute Fail Safe

Room Thermostat Set at___________°F Room Temp Holding at____________°F

FINAL Evaporator Superheat________°F Sight Glass Clear________ Pumpdown OK________

CONDITION Compressor Superheat________°F Compressor Oil Level________Glass

Discharge Line Temperature________°F Suction Pressure________PSIG

Start-Up By___________________________ Company____________________ Phone_________________

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REFRIGERATION SYSTEM SERVICE RECORD

Customer_______________________________ Job Name_________________________________________

City/State_______________________________ System No.___________________ Date_______________

Condensing Unit Model No.___________________________________ Serial No._______________________

Evaporator Model No._____________________________ Qty.______ Serial No._______________________

Room Name________________________ Design Room Temp_______°F Actual Room Temp________°F

Date System was Installed_______________ Product Stored___________________ Total Pounds________

Routine/Scheduled Preventive Maintenance o Service Call o Outdoor Ambient________°F

Service Requested___________________________________________________________________________

___________________________________________________________________________________________

Service Performed____________________________________________________________________________

___________________________________________________________________________________________

___________________________________________________________________________________________

Design Voltage______________________ Actual Voltage________________ Refrigerant R-__________

Electrical Specplate Test AmpsComponent Amps L1 L2 L3

Compressor __________ _________ _________ _________

Condenser __________ _________ _________ _________

Evaporator __________ _________ _________ _________

Defrost Htr. __________ _________ _________ _________

Evaporator Suction Temp__________°F Evaporator Suction Pressure__________PSIG

Convert PSIG to__________°F Evaporator Superheat__________°F

Compressor Suction Temp__________°F Compressor Suction Pressure__________PSIG

Convert PSIG to__________°F Compressor Superheat__________°F Ambient Temp__________°F

Compressor Discharge Pressure__________PSIG Compressor Discharge Line Temp__________°F

Compressor Oil Level________Glass Sight Glass Clear________ Sight Glass Dry__________

Cond Coil Clean_______ All Cond Fans Operate________ Liquid Temp Leaving Cond Unit________°F

Room Thermostat Set at__________°F Room Temperature Holding at___________°F

Evaporator Coil Clean__________ Drain Pan Clean________ Fan Blades/Guards Clean________

All Evap Fans Operate_________ Room Air Circulation OK________ Defrosting OK________

System Pumpdown OK_________ Cooler and Equipment in Safe Condition__________________________

System Notes__________________________________ Serviced by _____________________________

______________________________________________

______________________________________________

______________________________________________

______________________________________________

______________________________________________

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TROUBLE-SHOOTING REFRIGERATION SYSTEMSPROBLEM POSSIBLE CAUSES POSSIBLE CORRECTIVE ACTION

1. Fused disconnect switch or circuit 1. Close switch and / or breaker.

breaker open.

2. Blown fuse or tripped breaker. 2. Check for reason and repair. Replace fuse after

correcting problem.

3. Low line voltage. 3. Check line voltage; if more than 10% from

compressor marking, correcting is necessary.

4. Compressor motor protector open. 4. Motor protector automatically resets. Allow time

for compressor to cool down so protector will reset.

COMPRESSOR Restart and check for reason overheat occurred.

WILL 5. Defective compressor contactor. 5. Replace contactor.

NOT 6. Open room thermostat. 6. Check room temperature. If temperature is proper,

RUN wait for thermostat to close.

7. Open low pressure control. 7. Check low pressure control settings. See page 20

for initial settings and adjust as required.

8. Open defrost timer. 8. Check defrost timer for proper operation. Replace

if defective.

9. Open oil failure switch. 9. Check for causes of low pressure and reset switch.

10. Liquid line solenoid will not open. 10. Check holding coil; replace if defective.

11. Compressor motor defective. 11. Check motor for open circuit, short circuit,

grounded windings or burn-out.

12. Loose wiring. 12. Check all wire terminals and tighten as necessary.

1. Flooding of liquid refrigerant into 1. Check expansion valve superheat setting.

COMPRESSOR crankcase.

NOISY 2. Compressor hold-down nuts too 2. Loosen compressor hold-down nuts until

OR tight. compressor floats freely on mounting springs.

VIBRATING 3. Scroll compressor rotation sensitive. 3. Rewire for reverse rotation.

4. Worn or damaged compressor. 4. Replace the compressor.

1. Too much refrigerant. 1. Remove excess refrigerant.

HIGH 2. Non-condensibles in system. 2. Remove non-condensibles from system.

HEAD 3. Dirty condenser coil. 3. Clean condenser coil.

PRESSURE 4. Condenser fan not running. 4. Check electrical circuit and fuse. Check fan cycling

controls.

5. Discharge valve partially closed. 5. Open valve.

1. Improper suction pressure regulator 1. Check regulator setting. Reset if incorrect.

setting.

HIGH 2. Thermostatic expansion valve 2. Check bulb location and clamping.

SUCTION pressure limit feature incorrect Adjust superheat.

PRESSURE or inoperative. Overfeeding. Replace expansion valve power head.

3. Damaged valves in compressor. 3. Replace valve plate or compressor.

4. Worn piston rings and/or cylinder. 4. Replace compressor.

5. Room load too large. 5. Reduce the load or add more equipment.

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TROUBLE-SHOOTING REFRIGERATION SYSTEMSPROBLEM POSSIBLE CAUSES POSSIBLE CORRECTIVE ACTION

1. Insufficient refrigerant. 1. Check system for leaks. Repair leaks and add

LOW refrigerant.

HEAD 2. Faulty condenser temperature 2. Check condenser controls and reset to obtain desired

PRESSURE controls. condensing temperature.

3. Damaged valves in compressor. 3. Replace valve plate or compressor.

4. Worn piston rings and/or cylinder. 4. Replace compressor.

1. Insufficient refrigerant. 1. Check system for leaks. Repair leaks and add

refrigerant.

2. Unit cooler iced up or air flow 2. Check defrost system. Clean the coil.

LOW restricted. Check fan operation. Check air flow.

SUCTION 3. Plugged liquid line filter-drier. 3. Replace filter-drier or cartridges.

PRESSURE 4. Plugged suction filter. 4. Replace the suction filter.

5. Improper suction pressure 5. Check setting and correct as required.

regulator setting.

6. Expansion valve superheat too 6. Adjust valve for proper superheat or replace the

high or valve too small. expansion valve if too small.

1. Insufficient oil in system. 1. Thoroughly defrost evaporator. After defrost,

LOSS OF observe level, add oil. Check for leaks.

OIL Check lines for proper slope and traps.

2. Compressor short cycling. 2. Check low pressure control settings.

3. Defective oil pressure control. 3. Replace oil pressure control.

OR 4. Loose fittings on pump housing, 4. Check and tighten system. Check bottom plate on

compressor or oil lines. compressor.

5. Too much liquid refrigerant in the 5. Adjust expansion valve for higher superheat.

LOW OIL crankcase. Check crankcase heater.

PRESSURE 6. Plugged suction oil strainer. 6. Clean oil strainer.

7. Worn oil pump. 7. Replace the oil pump.

8. Worn compressor bearings. 8. Replace the compressor.

ICE 1. Defrost time is too long. 1. Adjust defrost termination thermostat.

BUILD UP 2. Too many defrost. 2. Reduce number of defrost.

ON CEILING, 3. Defective fan delay, defrost 3. Replace the defective component.

EVAPORATOR termination, or timer.

GUARDS OR 4. Voltage too high. 4. Reduce voltage to defrost heaters.

FAN BLADES 5. Ambient air leaks into room. 5. Seal all air leaks.

1. Coil temperature not getting high 1. Check heater operation. Check termination

COIL NOT enough during defrost, or defrost temperature. Adjust defrost thermostat for longer

CLEARING cycle too short. defrost.

DURING 2. Not enough defrost per day. 2. Set timer for more defrost.

DEFROST 3. Defective defrost controls or timer. 3. Replace defective component.

4. Voltage too low. 4. Increase voltage to defrost heaters.

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SYSTEM MAINTENANCE

Remove all leaves, grass, paper, lint, fluff, soil, feathers, cottonwood hair, or other materials fromthe condenser coil with a brush, blower, or vacuum. Grease and dirt removal may requirewashing with a coil cleaning detergent. Always rinse thoroughly with clean water after usinga chemical cleaner. Do not use cleaners containing ammonia. The coil must be kept clean atall times. Be sure the condenser fans are operating and the air flow is not restricted. Keep thecondensing unit area clean.

There is additional oil installed in the compressor to allow for a limited amount to circulatethroughout the system with the refrigerant. The oil is clear and can be difficult to see if above theoil level glass. The longer the compressor runs the lower the oil level may go. The oil level mayapproach the bottom of the glass before the system cycles off or a defrost occurs. After an offcycle or defrost period, the oil normally returns to the compressor. Once the room is down todesign temperature the oil level range should be about 1/8 to 5/8 glass.

Excess oil is dangerous to the compressor. Do not add oil just because the oil safety trips out.Thoroughly check out the loss of oil or oil pressure on trouble-shooting, page 27, before addingoil. Correct any condition that prevents oil return to the compressor. Visually check the oil pump,oil lines, and compressor bottom plate area for oil leaks.

Add only lubricant approved by the compressor manufacturer. Polyol ester, “POE”, syntheticlubricant must be used with R-404A and R-507 systems. Take caution not to fill above 1/2 glass.POE lubricants quickly absorb moisture from the atmosphere. The system must be kept sealedas much as possible to prevent moisture contamination.

Check the system pressures and temperatures on a regular basis to be sure they are within theguidelines recommended on page 23. Refer to trouble-shooting on page 26 and 27 forsuggestions.

Evaporators should be checked frequently and cleaned of dirt and grease accumulation.Disconnect electrical power to the evaporator when inspecting or cleaning. The fan blades, fanguards and coil may require frequent cleaning. Do not use ammonia or other cleaning chemicalsthat are corrosive to copperor aluminum. The drain pan should be lowered for inspection andthoroughly cleaned to prevent buildup of foreign materials. Make sure the drain connection areais clean and clear.

Make sure all motors and fans are in good operating condition. If uneven frosting of the coil isobserved, look for air leaking into the room. Eliminate all air leaks for optimum evaporatorperformance and energy savings. Do not leave the access panels off after adjustment or service.The access panels should always be in place when the evaporator is operating. Keep cold roomdoors closed when possible.

TO INQUIRE OR ORDER REPLACEMENT PARTS

Telephone (256) 259 – 7400 Fax (256) 259 – 7478

1. Provide the complete Model Number and Serial Number of the unit.2. Provide a detailed description of the part with any model, diameter, HP, or other markings.3. State the quantity you are ordering.4. Advise special shipping methods, routes, procedures, or instructions with ship to address.5. Provide complete and accurate data to insure prompt and accurate delivery.6. Compressors and compressor parts must be obtained from your local wholesaler.