carrier cold room calculaton.pdf

REFRIGERATIONSELECTION GUIDE

For Condensing Units & Unit Coolers

Today’s Solution To Your Total Range Of

Refrigeration Needs.

© Carrier Corporation 10/91, Rev A 06/03 www.totaline.com Literature Number: 570-545


Introduction: Using The Totaline® Refrigeration CondensingUnit Selection Guide .............................................................. 3

Section One: Performing A Job Survey and DeterminingRefrigeration LoadJob Survey ...............................................................................4Site Conditions .........................................................................4Refrigeration Load Calculations ............................................... 4Refrigeration Load Segments ...................................................4Transmission (Wall Load) .........................................................4Air Change or Ventilation Load ................................................ 4The Product Load .................................................................... 5

Other ConsiderationsSpecific HeatLatent HeatHeat of RespirationProduct Load Formulae

Miscellaneous Loads ............................................................... 5Safety Factor and Other Considerations .................................. 6Total Load ................................................................................ 6Load Calculation Forms 8

For rooms below 32°F (sample) ....................................... 8For rooms below 32°F (blank) .......................................... 9For rooms above 32°F (blank) ........................................ 10For rooms above 32°F (sample) ......................................11

Section Two: Equipment Selection ConsiderationsEvaporator Coil Selection - System TemperatureDifference and Relative Humidity ...........................................12Run Time and Defrost Operations ..........................................12

Electric DefrostHot Gas DefrostWater DefrostGeneral Defrost Considerations

Compressor / Condensing Unit Selection .............................. 13Evaporator Selection ...................................................... 13 - 15

Gravity Fin CoilsGravity Booster Unit Coolers (low air units)Space CoolersUnit CoolersProduct Coolers

Evaporator Layout ................................................................. 15Selecting Thermal Expansion Valves ..................................... 15Selecting A Heat Exchanger ................................................... 15

Section Three: TablesTable 1 - “U” Values of Various Insulations .......................... 16Table 2 - Transmission Heat Gain Factors .............................16Table 3 - Average Air Changes Per 24 Hours

For Storage Rooms ................................................ 17Table 4 - Heat Removed In Cooling Air To

Storage Room Conditions ...................................... 18Table 5 - Storage Requirements and Properties

of Perishable Products ................................... 19 - 23Table 6 - Approximate Heat of Respiration Rates at

Temperature Indicated ........................................... 24Table 7 - Heat Equivalent of Electric Motors ......................... 25Table 8 - Heat Equivalent of Occupancy ............................... 25Table 9 - Summer Outdoor Design Data ........................25 - 26Table 10 - Operating Conditions for Fur Storage .....................27Table 11 - Insulation Requirements for Storage Rooms ......... 27Table 12 - Suggested Freezer Temperatures °F ........................27

2

Table of Contents


The Totaline® Refrigeration Selection Guide presents data andexamples to assist the installing contractor or engineer whenpreparing actual refrigeration load estimates and selectingrefrigeration equipment.

Section One of this publication provides a detailed explanationof the factors that determine a refrigeration load. This will beof significant assistance when completing the easy-to-useLoad Calculation Forms included in this section. In addition toa perforated blank form for refrigeration applications belowand above 32°, examples of completed load estimates arepresented. Blank forms are also available in pads from yourTotaline representative.

Once the refrigeration load is determined, proper equipmentmust be selected. Section Two is a guide to selecting the mostappropriate equipment to the particular application.

Section Three contains handy refrigeration reference tablesthat will be most helpful in pinpointing specific needs. Many of the tables in Section Three are referenced in the first twosections and the remainder are included for additionalreference.

This manual is offered as a general tool for industry use andfor anyone designing systems. Certain tabular data has beenduplicated in full or part from ASHRAE Handbooks. All otherdata has been compiled by the Replacement ComponentsDivision of Carrier Corporation, Syracuse, NY. Installers,engineers or others using this manual should exercisejudgement when specifying refrigeration equipment forspecific applications. The Replacement Components Division isnot responsible for any use made of this text.

Thank you for considering Totaline refrigeration condensingunits. Totaline products are engineered and manufactured withthe utmost in quality control. The Replacement ComponentsDivision of Carrier Corporation is ready to support all yourneeds with our full range of Totaline Service Parts.

3

Introduction: Using The Totaline® Refrigeration Selection Guide


When reading this section refer to Load Calculation Formsstarting on page 8.

Job SurveySite ConditionsThe calculation of the transmission, product, internal and air change load segments will be discussed in detail. Before theload can be estimated, however, a comprehensive analysis ofsite conditions must be made to assure an accurate evaluationof the total refrigeration load. This job survey shoulddetermine all pertinent job site information including:• Design ambient temperatures (see Table 9)• Storage area temperature and humidity requirements• Storage area dimensions and type of construction,

insulation, exposure, etc.• Type and amount of stored product• Electrical service requirements• Any miscellaneous loads including people, lights,

appliances, etc.Based on this data, the total heat load of the refrigerated space can be calculated by adding the totals of the four loadsegments: transmission, product, internal and air change. It iscommon practice, and recommended, to add a 10% safetyfactor to the calculated refrigeration load.

Refrigeration Load Calculations Refrigeration Load SegmentsThe primary function of refrigeration is to maintain conditions of temperature and humidity that are required by a product orprocess within a given space. To perform this function,equipment of the proper capacity must be installed andcontrolled on a 24-hour basis. The equipment capacity isdetermined by the actual instantaneous peak loadrequirements. Generally, it is impossible to measure the actualpeak load within a refrigerated space. These loads must beestimated. The total refrigeration load is the total of thefollowing “load segments”:• Transmission Load - heat gain through walls, floors

and ceilings.• Air Change Load - heat gain associated with air entering

the refrigerated space, either by infiltration or ventilation.• Product Load - heat removed from and produced by

products brought into and stored in the refrigerated space.

• Internal Load - heat produced by internal sources such as lights, electric motors, and people working in the space.

Transmission (Wall Load)The wall or transmission load is the load caused by the refrigerated space being located adjacent to a space at ahigher temperature. Heat always travels from the warmer tothe cooler atmosphere. The sensible heat gain through walls,floors and ceilings will vary with the following factors:• Type and thickness of the insulation• Type of construction• Outside wall area in square feet• Temperature difference between the refrigerated space and

the outside ambient, adjusted to allow for solar heat load on any surface exposed to the sun.

The following explains the formulae used to calculate the transmission load.Thermal Resistance, R, is defined as the total resistance of a material to heat flow, expressed in (°F TD) (sq ft)/Btuh.(TD is temperature difference which is explained in SectionTwo, page 12.)Coefficient of Heat Transfer, U, is defined as the overall rate of heat transfer through a material, expressed in Btu/(hr)(sq ft) (°F TD).The overall heat transfer factors based on the actual wall construction can be calculated by the formula:• Q = A x U x TD, where Q = heat load, Btuh• A = sq ft area of the wall, roof, etc• U = the "U" factor for the wall expressed in °F between

the inside and outside wall surface.The tabulated heat gain factors, Tables 1 and 2, at intervals of overall temperature differences, can be used to simplifycalculations. These factors are expressed in Btu/sq ft/24 hours.Other ConsiderationsFor small walk-in coolers and freezers, where there are nounusual requirements, the wall load may be taken as the totaloutside surface multiplied by the appropriate wall heat gainfactor based on the ambient air temperature difference.Latent heat gain due to moisture transmission through walls,floors, and ceilings of modern construction refrigeratedfacilities is negligible and can be ignored.

4

Section One: Performing A Job Survey & Determining Refrigeration Load


Air Change or Ventilation LoadEach time a door is opened to a refrigerated room from an adjacent unrefrigerated space, some outside air will enter theroom. This untreated warm moist air will impose an additionalrefrigeration load and must be taken into account in the heatload calculation. Usually, the infiltration air's moisture contentis more than that of the refrigerated space. As this air iscooled to the space temperature, the moisture will condenseout of the air. This imposes both a sensible and latent heatload in the space which must be removed by the refrigerationequipment.Infiltration air quantities are difficult to determine accurately. Usually, a number of air changes per day are estimated. Table3 indicates the number of air changes that may be expected ina given size of room over a 24-hour period. The data containedin this table have been determined by experience and may beused with confidence. Please note that the air change factorsvary for rooms above and below 32°F. For rooms below 0°F,some further reduction of the air changes may be considered.There is usually less traffic involved in a 0°F room, with lessair movement resulting.Having determined the number of air changes to be expected, the room volume is then multiplied by the number of airchanges. To obtain the infiltration load, a factor is thenobtained from Table 4 and is applied to the total volume of air.The Btu/cubic foot factors in Table 4 are based on the dry bulbtemperature and the relative humidity of the infiltration air.

The Product LoadThe heat gain caused by the product must be considered in the total refrigeration load calculation. The product heat gainwill include some or all of the following:1.The load due to the product being placed in the

refrigerated space at a higher temperature than the design refrigerated space.

2.The heat removed by freezing or chilling the product.3.The heat of respiration caused by chemical reactions

occurring in the product.Specific HeatA product cooling from its initial temperature requires the removal of sensible heat. Sensible heat is heat that can bedetected and recorded on a dry bulb thermometer. Thesensible heat to be removed is known as the specific heatwhich is the amount of heat in Btus that must be removed toreduce the temperature of the product 1°F. The specific heatwill vary with the type of product and is different above andbelow 32°F. Specific heat figures are listed in Table 5 forvarious product types.

This calculation is applied to all products that must be frozen.The latent heat of fusion of any product is that of water - 144Btu/lb—multiplied by the percentage of water content of theproduct. Actual corrected latent heat figures for variousproducts are shown in Table 5.

Heat of Respiration Certain food products experience chemical changes after storage. This is true of most fruits and vegetables, and somedairy products. This chemical change results in heatproduction which must be considered in the load calculation. The heat of respiration occurs at temperatures over 32°F and varies depending on the product and the storage temperature.Table 6 indicates the heat of respiration for various products atcommon storage temperatures. Please note that this heat loadincreases considerably at higher temperatures.

Product Load Formulae

Latent HeatWhen the product is cooled to a temperature of 32°F or lower, the latent heat load is also a part of the product load. Thisprocess is called the latent heat of fusion. The latent heat loadis the quantity of heat involved in changing the state of asubstance without changing its temperature.

5

Infiltration Air Formula:Infiltration Btu/hr = Room Volume, Cubic Feet x

Air Change Factor (Table 3)

Sensible load (Btu/24 Hours) = Specific heat ofproducts (Table 5) x temperature reduction of products°F x lbs of productLatent heat of fusion (Btu/24 Hours) = Latent heat of product (Table 5) x lbs of productHeat of respiration (Btu/lbs/24 Hours) = Heat of respiration of product (Table 6) x lbs of product

For example, 144 Btu’s must be removed to freeze apound of water. In the process, the pound of water at32°F becomes a pound of ice at 32°F.


Miscellaneous LoadsAll electrical energy used by lights, motors, heaters, etc., located in the refrigerated area, must be included in the heatload. To calculate these loads:

Motors - The heat input from motors vary with the motor size,BHP output, efficiency and whether it is located within, oroutside of, the refrigerated space.The heat equivalent of one BHP is 2545 Btu/hr. Motor efficiencies vary from 40% and less for small fan motors to80% or more for integral horsepower motors. The motoroutput will be its BHP x 2545 Btu/hr x hours of operation.If the motor is located inside the refrigerated area, divide its output by its efficiency. If the motor is located outside therefrigerated area, its inefficiency will be dissipated outside,then only its output will figure in the room load. If the motor islocated in the room and the load is outside, only theinefficiency will be added to the room load. Multiply the outputby (1 - efficiency).For motors rated in Watts output, divide by 746 to obtain the heat equivalent horsepower rating. See Table 7, HeatEquivalent of Electric Motors.Occupancy Load - People working in a refrigerated storage area dissipate heat at a rate determined by the roomtemperature. The heat load added to the room equals thenumber of people, the hours of occupancy and heatequivalent per person. Multiple occupancies of short durationwill carry additional heat into the room. See Table 8, HeatEquivalent of Occupancy.

Safety Factor and Other ConsiderationsA minimum 10% safety factor is normally added to the total refrigeration load to allow for minor omissions andinaccuracies, but do not assume this is adequate to take careof the evaporator fan load. (Additional safety or reservecapacity may be available from the compressor running timeand average loading.)The Total Load with safety factor does not include the evaporator fan or defrost loads, which must be evaluated andadded to the basic load to arrive at the total load for the finalselection of the refrigerating equipment. Tables and datarequired for calculating loads are tabulated for quick reference.

Total LoadTo arrive at the total Btu/24 hr load, total all four main sources of heat gain and add a 10% safety factor as recommended.For system running times and defrost information, see Section Two - Equipment Selection Considerations, page 12. If furtherassistance is required, please contact your Totaline distributor.

6

Lights = Total lighting wattage x hours in use x 3.41Btu/Watt for incandescent or 4.2 for fluorescent lights.Coolers and freezers = 1 to 1-1/2 Watts per square foot of floor area. Allow up to double this amount forwork areas


LOADCALCULATION

FORMS

7

LOAD CALCULATION FORMFor Rooms Below 32°F

SITE CONDITIONS1. Describe the application2. What are the outside room dimensions (ft.)?(w) x (l) x (h)3. Describe the insulation Type Thickness inches4. What is the overall wall thickness? inches5. What is the outside or surrounding air temperature? (Table 9) °F6. What is the storage room temperature? °F7. What is the temperature reduction? (subtract line 6 from line 5) °F8. What is the electrical load watts including lights and motors? watts9. How many people occupy this space?10. What is the total product weight?11. Product load information:

8

Customer Job Date

Address Estimator

FRED’S FROZEN FISH EXAMPLE #1 3/30/0134 CHARLES ST., PORTLAND, MAINE S.C.

FREEZER - FRESH FISH20 30 10

FIBERGLASS 66

ROOM 75-10

85500

02000 LBS / DAY

HADDOCK ARRIVING AT 50ºF,NO OUTSIDE WALLS

Prepared by DateLoad calculation pads are available from your Carrier representative (Literature Number 570-825)

LOAD CALCULATIONA. Transmission (Wall) Load

a. Exterior wall surface(w)__________ x (l) ___________ = __________(l) __________ x (h) __________ = __________(w) _________ x (h) __________ = __________

__________ x 2 = __________ sq ftb. Table 2 Btu load/sq ft/24 hours = __________________________

a. ______________________ x b. ______________________ = _______________________ Btu / 24 hoursB. Air Change (Infiltration Load)

a. Interior room volume _______ x ______ x _______ = ________ cu ft(inside room dimensions)

b. Table 3 air changes per 24 hours = ____________c. Table 4 Btu/cu ft = ____________

a. _____________ x b. _____________ x c. ______________ = _______________________ Btu / 24 hoursC. Product Load

1. Product temperature reduction load above freezinga. Total product weight = _____________ Ibsb.Product temperature reduction to freezing = _______________ °Fc. Table 5 specific heat above freezing = _______________

a. _____________ x b. _____________ x c. ______________ = _______________________ Btu / 24 hours2. Latent Heat of Fusion Load

a. Total product weight = _____________Ibsb.Table 5 latent heat of fusion = _____________Btu/lb

a. ______________________ x b. ______________________ = _______________________ Btu / 24 hours3. Product temperature reduction load below freezing

a. Total product weight = __________ Ibsb.Product temperature below freezing = ______________ °Fc. Table 5 specific heat below freezing = ______________

a. _____________ x b. _____________ x c. ______________ = _______________________ Btu / 24 hoursD. Miscellaneous Load

a. Electrical load (Watts) __________ x 3.42 x 24 = _______________________ Btu / 24 hoursb. Number of occupants __________ x (Table 8) __________ x 24 = _______________________ Btu / 24 hours

E. Total Load without safety factor (add right column) .............................. = _______________________ Btu / 24 hoursF. Safety Factor (add 10% of Btu load per 24 hours) ................................. = _______________________ Btu / 24 hoursG. Total Load with safety factor (Add E and F) ........................................... = _______________________ Btu / 24 hoursREFRIGERATION Total Btu Per 24 Hours = = BTU / HR LOAD

LOAD: Compressor Running Time (See page 12)

FACILITY LAYOUT(Note: Detail all relevant construction features)

20 30 60030 10 30020 10 200

1100 2200142.8 (INTERPOLAYTION)

2200 142.8

29 19 9 4959

5.62.4

4959 5.6 2.4

200018

0.852000 18 0.85

2000117

2000 117

200042

0.442000 42 0.44

5000 ------------

795,75020

314,160

66,649

30,600

234,000

36,960

41,0400

723,40972,341

795,75039,788

LOAD CALCULATION FORMFor Rooms Below 32°F

9


Customer Job Date

Address Estimator









1. Product temperature reduction load above freezinga. Total product weight = _____________ Ibsb.Product temperature reduction to freezing = ______________ °Fc. Table 5 specific heat above freezing = ____________

a. _____________ x b. _____________ x c. ______________ = _______________________ Btu / 24 hours2. Latent Heat of Fusion Load

a. Total product weight = _____________Ibsb.Table 5 latent heat of fusion = _____________Btu/lb

a. ______________________ x b. ______________________ = _______________________ Btu / 24 hours3. Product temperature reduction load below freezing

a. Total product weight = __________ Ibsb.Product temperature below freezing = ______________ °Fc. Table 5 specific heat below freezing = ______________

a. _____________ x b. _____________ x c. ______________ = _______________________ Btu / 24 hoursD. Miscellaneous Load


E. Total Load without safety factor (add right column) .............................. = _______________________ Btu / 24 hoursF. Safety Factor (add 10% of Btu load per 24 hours) ................................. = _______________________ Btu / 24 hoursG. Total Load with safety factor (Add E and F) ........................................... = _______________________ Btu / 24 hoursREFRIGERATION Total Btu Per 24 Hours = = BTU / HR LOAD

LOAD: Compressor Running Time (See page 12)


LOAD CALCULATION FORMFor Rooms Above 32°F

10


Customer Job Date

Address Estimator









1. Product temperature reduction load a. Total product weight = _____________ Ibsb.Product temperature reduction to freezing = ______________ °Fc. Table 5 specific heat above freezing = ____________

a. _____________ x b. _____________ x c. ______________ = _______________________ Btu / 24 hours2. Respiration Heat Load

a. Total product weight = _____________Ibsb.Table 6 respiration heat/lb = _____________Btu/lb

a. ______________________ x b. ______________________ = _______________________ Btu / 24 hoursD. Miscellaneous Load


E. Total Load without safety factor (add right column) .............................. = _______________________ Btu / 24 hoursF. Safety Factor (add 10% of Btu load per 24 hours) ................................. = _______________________ Btu / 24 hoursG. Total Load with safety factor (Add E and F) ........................................... = _______________________ Btu / 24 hours

REFRIGERATION Total Btu Per 24 Hours = = BTU / HR LOADLOAD: Compressor Running Time (See page 12)


LOAD CALCULATION FORMFor Rooms Above 32°F

11


Customer Job Date

Address Estimator

JOHN E. APPLESEED EXAMPLE #2 3/31/0112 CIDER ST., PITTSBURGH, PA L.S.

WALK-IN COOLER (APPLES)20 30 10

POLYURETHANE 46

9035

551000(10HR/DAY)

27000 LBS

FRESH APPLES ARRIVING AT 70ºFFROM ORCHARD









1. Product temperature reduction load a. Total product weight = _____________ Ibsb.Product temperature reduction to freezing = _______________ °Fc. Table 5 specific heat above freezing = _______________

a. _____________ x b. _____________ x c. ______________ = _______________________ Btu / 24 hours2. Respiration Heat Load

a. Total product weight = _____________Ibsb.Table 6 respiration heat/lb = _____________Btu/lb

a. ______________________ x b. ______________________ = _______________________ Btu / 24 hoursD. Miscellaneous Load


E. Total Load without safety factor (add right column) .............................. = _______________________ Btu / 24 hoursF. Safety Factor (add 10% of Btu load per 24 hours) ................................. = _______________________ Btu / 24 hoursG. Total Load with safety factor (Add E and F) ........................................... = _______________________ Btu / 24 hours

REFRIGERATION Total Btu Per 24 Hours = = BTU / HR LOADLOAD: Compressor Running Time (See page 12)


20 30 60030 10 30020 10 200

1100 220052.8 (INTERPOLAYTION)

2200 52.8

29 19 9 4959

7.21.78

4959 7.2 1.78

700035

0.877000 35 0.87

70000.45

7000 0.45

10002 895

520,49316

116,160

63,555

213,150

3150

34,20042,960473,175

47,318520,49332,530

X 1024


Now that the refrigeration load for a particular job site iscalculated, it is time to select the most suitable equipment forthe application. Section Two offers information that will helpmake equipment selection decisions. This information, usedtogether with product data and specifications frommanufacturers' literature, will result in an informed selectiondecision.

Evaporator Coil Selection - System Temperature Difference and Relative HumidityWhen selecting an evaporator coil, the temperature difference, or TD, between the room and the saturated suctiontemperature dictates the relative humidity in the space(assuming the room is properly sealed). The closer thetemperature difference between room and suctiontemperatures in selecting the evaporator, the larger theevaporator and the higher the relative humidity in the room.Conversely, a large system TD reduces the size of the evaporator and causes it to do more drying and thereforelowers the relative humidity.The following table can be used as a guide. Knowing the product relative humidity requirement, select the evaporator as follows:

Relative Humidity % (RH) TD (°F)

Over 90 880-90 1070-80 1550-70 20

Too low relative humidity will result in excessive weight loss inthe product as well as surface deterioration. Too high relativehumidity speeds the growth of bacteria and surface slime. SeeTable 5 for recommended relative humidity values for differentproducts.There is a slightly different problem associated with freezers. In order to avoid excessive frost accumulation on the coil, andto prevent product dehydration during long term storage, mostevaporators are selected for 10°F TD.

Run Time and Defrost OperationsWhen the design suction temperature is over 30°F, a defrost cycle is not normally required, and it is common practice toselect equipment on a 20- to 22-hour compressor operation.For suction temperatures below 30°F and room temperaturesover 35°F, off-cycle (air defrost) can generally be used. Thisinvolves cycling the compressor off with a time clock while theevaporator fans remain in operation and room air melts the iceon the coil. For every two hours of compressor operation, onehour of air defrost time is needed. Therefore, compressorselection is based on 16 hours per day.

For suction temperatures below 30°F and rooms below 35°F, electric defrost, hot gas defrost or water defrost is required.With these positive methods of defrost, equipment selectioncan be based on longer compressor operation, with 18 to 20hours most common. However, this depends on the type ofequipment used and the latent load in the storage. A modernunit cooler or product cooler in a tight room with averagelatent load, can be selected on 20 hour operation.The type of defrost used is generally a matter of eithercontractor or owner preference. Different geographic regionstend to use one particular type of defrost more frequently.As a rule, electric defrost is more common than hot gas, andhot gas more common than water defrost.Electric DefrostElectric defrost is the most common method in use today.Equipment cost is about the same as with hot gas but installedcost can be lower. Operating cost is about 15% higher withelectric defrost than with hot gas and a fair amount of heatand moisture is released in the room during defrost.Hot Gas DefrostHot gas defrost is still the most efficient method of defrostingregardless of storage temperature but, unfortunately, mostcontractors are reluctant to use it. Defrost is very quick withminimum room temperature rise. Hot gas defrost, however,requires care to ensure that the compressor is protectedagainst liquid slugging.Water DefrostWhile not very common, water defrost can be used on bothmedium and low temperature storages. Water must be at least 50°F and is sprayed on the coil at a rate of about 3gpm/square foot of coil for five to 15 minutes, depending on severity of frosting. Water defrost is fast and efficient butsome moisture is re-released into the room. These systemsalso require more maintenance than electric or hot gassystems.General Defrost ConsiderationsBecause of high suction pressure (and high load) after defrost, compressor selection must be checked to see that it canoperate in a higher range than the actual design point. If not, acrankcase pressure regulator may be required to keep suctionpressure down to acceptable values. If this is the case, anaccumulator should also be used. This is very important for ablast freezer. On large air defrost systems (gravity coil, forexample) it is a good idea to have solenoids in the liquid andsuction lines so refrigerant will not migrate during defrost. Inaddition, large fin coil installations are often split into sectionswith a thermostat for each section to compensate for unevenroom loading.It is also recommended that a pump down system be used for both off-cycle and all defrost periods.

12

Section Two: Equipment Selection Considerations


Compressor/Condensing Unit SelectionThe four main types of compressors used in commercial refrigeration today are:• Open - belt driven (low speed, 500-1750 rpm)• Open - direct driven (medium speed, 1160 or 1750 rpm)• Semi-hermetic (1750 rpm)• Hermetic (welded, 3500 rpm)The compressor type used is often a matter of personal preference but it is important to be aware that compressor lifedecreases with increased speed and increased condensingtemperature.On commercial refrigeration applications, compressors are most commonly used with air-cooled condensers. They arealso used with water-cooled condensers and occasionally withevaporative condensers. Water restrictions in recent years and simpler maintenance are the reasons for the popularity ofair-cooled systems.The air-cooled condenser may be an integral part of the compressor unit (air-cooled condensing unit) or it may beremotely located (on the roof, for example).Compressor/condensing units are generally classified as high, medium or low temperature. Approximate evaporatingtemperatures are:• High +30°F to +50°F• Medium -10°F to +30°F• Low 40°F to -10°FA choice of refrigerant, R-12, R-22 and R-502 is available, depending on the application.Knowing the room load, room temperature and desired suction temperature (room temperature - TD = suctiontemperature), a condensing unit can be selected. As the range of models (capacities) is far more limited in condensingunits than in evaporators, it is common practice to select theclosest condensing unit size that will do the job, then selectthe evaporators to balance with the condensing unit selectedat the correct TD.When it is possible that the compressor may occasionally be the coldest spot in the system, crankcase heaters should beused. Unloading is seldom (if ever) used on commercialrefrigeration systems.Refrigerant receivers are generally used and are sized to hold from 80% to the complete system operating charge.In any critical application, use two completely independent systems. In all cases, every room should be on a separate andindependent system.

Evaporator SelectionThe spacing of the fins on the evaporator coil must be considered for a particular application. While high fin density(12 fins/inch) gives increased coil capacity, it also increasesthe problem of dirt and frost collection. In the majority ofcommercial refrigeration applications, the fin spacings usedare 8, 6 and 4 fins/inch. Generally, 8 fins/inch is used down to+32°F coil temperature while spacings of 4 and 6 fins/inch areused whenever frost will be present. The closer the fins aretogether, the more rapidly the coil capacity will fall off as thefrost builds up.On most low temperature applications, 6 fins/inch can be used as long as the evaporator capacity is reduced by 15% (x 0.85),when making the selection. This 15% frost reduction is a moreaccurate representation of the unit capacity averaged over thefour to six hours between defrost cycles. For minimumdowntime, base selection on a 4 fin/inch coil and its normalcapacity reduced by 5% (x 0.95). In most cases, holdingfreezers are selected with 6 fin/inch coils while blast freezersuse 4 fins/inch.Once the space and product loads have been established, select the evaporator type most suitable for the application.This selection will depend on:• Storage temperature• Relative humidity• Air velocity• Room size and shapeRefer to Table 5 for recommended storage temperature and relative humidity. As most rooms handle more than oneproduct, compromise may be necessary. Next, establish whatform (if any) of defrost will be required.The following describes the various types of evaporators that are available and descriptive data on their use.

Gravity Fin Coils

13

Outlet velocity about 60 fpm

Temperature range = 35°F and above

Capacity range @ 10°FTD = 100-19,000 Btu/hr/unit

Air flow range = 0


Gravity fin coils are used in rooms requiring little or no airflow. They are commonly used in meat aging rooms as theyproduce the best meat surface texture and appearance. Theyare also used in beef sales coolers since they have no fans and operate silently. Although not very common in currentdesigns, some packing houses and supermarkets still preferthis type of unit.These coils are installed between-the-rails in meat coolers, as well as in poultry storages, cut flower rooms, etc. Mostgravity coils are used in high-humidity applications.

Gravity Booster Unit Coolers (low air units)

The application of gravity boosters are similar to gravity fincoil applications. Gravity boosters usually result in a lower firstcost to the owner and are, therefore, gradually replacing thefin coil. They are also installed between-the-rails in meatrooms as well as meat cutting and packaging rooms, cutflower boxes, fruit and vegetable storages and ice storages.Gravity booster unit coolers are available with electric defrostfor applications in the 28-34°F and without defrost for roomsover 34°F. The gravity booster has a power operated fan toprovide a more positive air flow than the gravity coil.

Space Coolers

Unit coolers are the most common type of evaporator in usetoday. Unit coolers are used at all temperatures, on all types ofstorages and are available with hot gas or electric defrost.These units handle larger quantities of air than gravityboosters and are able to “throw” the air 30 to 40 feet with aone foot drop. The most common application is the food storewalk-in freezer or general purpose cooler. They are also usedin blast freezers and some models are available with low pitchfans for use as gravity boosters. Unit coolers are generallyconsidered the most economical evaporator on a first-costbasis and are adaptable to many applications.

Product Coolers

Product coolers are the largest and the most versatileevaporators and are generally found on larger jobs. They areavailable for all refrigerants and with all types of defrostsystems, air quantity, coil rows, fin spacing and coil area.Some models are available as propeller fans (free blow) aswell as the standard centrifugal fan version. They arecommonly used with duct work and models are available forfloor mounting as well as ceiling suspension. While moreexpensive in first cost than unit coolers, product coolers areoften a necessity in larger storages and are commonly foundin blast freezers.When using electric defrost, horizontal type product coolers must be used. Vertical type product coolers with electric defrostwill result in “stack effect.” This causes extensive convectioncurrents which adversely affect the defrost operation.After identifying the type of evaporator to use, the actual selection must be made to balance with the condensing unitselection. The condensing unit should be selected first becauseonly a fixed number of condensing units sizes are available,while there is virtually an unlimited selection of evaporators.

14

Outlet velocity less than 150 fpm


Capacity range @ 10°F TD = 4500-27,000 Btu/hr/unit

Air flow range = 200 fpm face velocity or 1200 cfm/ton



Air flow range = 200-500 fpm face velocity or 1200 cfm/ton



Air flow range = 500-600 fpm face velocity or 1500-2000 cfm/ton


Capacity range @ 10°F TD = 26,000-385,000 Btu/hr/unit

Air flow range = 600 fpm face velocity or 1600-2500 cfm/ton

Applications for space coolers are very similar to gravity fincoils and gravity boosters but space coolers are much moreversatile. Both air flow and outlet velocity are variable. Unitsare available with hot gas and electric defrost as well as forammonia. Other applications include breweries, cheesefactories and general storage rooms.

Unit Coolers


When selecting hot gas or electric defrost units, allow for coilfrosting and for the capacity rating of the unit to be reducedaccordingly. With electric defrost units, where the heaters areinternally located in blank tubes, compared to a standard coil,the capacity must be reduced to allow for the loss of surface.Manufacturers usually recommend a rating correction factor for electric defrost coils. It is always good practice with anystorage (and particularly with freezers) to have two completelyindependent systems. In the event of a breakdown of onesystem, the other unit will slow down the temperature rise inthe room until the other system is repaired and placed backinto service.

Evaporator LayoutEvaporator layout is much more important than many designers realize. Follow these general, but important, rules:1. Air pattern must cover the entire room.2. Never locate evaporators over doors.3. Know the location of aisles, racks etc.4. Locate near compressors for minimum pipe runs.5. Locate near condensate drains for minimum run. The size and shape of the storage generally dictates the type and location of the evaporators. The illustrations below showsome typical examples.

Selecting Thermal Expansion ValvesSelecting and installing thermal expansion valves are of utmost importance for the best coil performance. Valvecapacity must be at least equal to the coil load rating but notoversized for the conditions. Any valve which is substantiallyoversized will tend to be erratic in operation and this willimpair both coil performance and rated capacity output.Always install liquid line strainers ahead of all thermalexpansion valves

Selecting A Heat ExchangerAlthough sometimes controversial in high temperature applications, it is generally agreed that in medium and lowtemperature refrigeration systems, heat exchangers, whenproperly applied, contribute the following to overall system performance:1. Sub-cooling the liquid refrigerant entering the thermal

expansion valve reduces the flash gas load of the evaporator inlet. It also increases the enthalpy difference of the refrigerant during its evaporating phase which produces more useful work in the evaporator.

2. In the process of heat exchanger sub-cooling, the heat extracted from the liquid refrigerant is transferred to the suction gas, thereby insuring a dry suction return to the compressor at an entering superheat level. This produces the best possible volumetric efficiencies for the refrigerant used.

3. The increase in suction line temperature will also reduce the possibility of sweating.

4. The use of a heat exchanger permits more open adjustment of the thermal expansion valve without risk of serious flood-back of liquid to the compressor under light or variable load conditions. At the same time, this assures the maximum utilization of evaporator surface.

In all low temperature applications, it is most important to correctly size and properly apply heat exchangers. Selectionsmust be based on accurate performance ratings checked outagainst the calculated design loads involved for eachevaporator or otherwise for the entire system. Care must alsobe taken to insure that both liquid and suction connections areproperly sized in order to reduce entrance and exit losses to aminimum. Recommended allowable suction line pressuredrops due to the heat exchanger vary from 0.50 psi maximumfor +20°F evaporator applications to 0.25 psi maximum for -40°F evaporator temperatures.

15


Material Thickness (Inches) "R" "U"

Polystyrene Foam 1 5.0 0 20Styrofoam "SM" 2 0 10

(Blue) 3 0 07Styrofoam Roofmate 4 0.05

(Blue) 5 0 046 0.0358 0.025

Polyurethane Foam 1 6.25 0.16Board 2 0.08

3 0.0554 0.045 0.0326 0.0278 0.02

Rigid Glass Fibre 1 4.0 0.25Styrofoam 1 3.57 0 28

Beadboard (White) 2 0.143 0.094 0.075 0.0556 0.0458 0.035

Table 2 - Transmission Heat Gain Factors (Btu/24Hours/Sq. Foot of Outside Surface)WALL INSULATION "U" FACTOR DESIGN TEMP. DIFF. °F*(FROM TABLE 1, ABOVE)

10 20 30 40 50 60 70 80 90 100.01 2.4 4.8 7.2 9.6 12.0 14.4 16.8 19.2 21.6 24.0.02 4.8 9.6 14.4 19.2 24.0 28.8 33.6 38.4 43.2 48.0.025 6.0 12.0 18.0 24.0 30.0 36.0 42.0 48.0 54.0 60.0.030 7.2 14.4 21.6 28.8 36.0 43.2 50.4 57.6 64.8 72.0.035 8.4 16.8 25.2 33.6 42.0 50.4 58.8 67.2 75.6 84.0.040 9.6 19.2 28.8 38.4 48.0 57.6 67.2 76.4 86.4 96.0.045 10.8 21.6 32.4 43.2 54.0 64.8 75.6 86.4 97.2 108.0.050 12.0 24.0 36.0 48.0 60.0 72.0 84.0 96.0 108.0 120.0.055 13.2 26.4 39.6 52.8 66.0 79.2 92.4 105.6 118.8 132.0.060 14.4 28.8 43.2 57.6 72.0 86.4 100.8 115.2 129.6 144.0.065 15.6 31.2 46.8 62.4 78.0 93.6 109.2 124.8 139.4 156.0.070 16.8 33.6 50.4 67.2 84.0 100.8 117.6 134.4 151.2 168.0.075 18.0 36.0 54.0 72.0 90.0 108.0 126.0 144.0 162.8 180.0.080 19.2 38.4 57.6 76.8 96.0 115.2 134.4 153.6 172.8 192.0.085 20.4 40.8 61.2 81.6 102.0 122.4 142.8 163.2 183.6 204.0.090 21.6 43.2 64.8 86.4 108.0 129.6 151.2 172.8 194.4 216.0.095 22.8 45.6 68.4 91.2 114.0 136.8 159.6 182.4 205.2 228.0.10 24.0 48.0 72.0 96.0 120.0 144.0 168.0 192.0 216.0 240.0.20 48.0 96.0 144.0 192.0 240.0 288.0 336.0 384.0 432.0 480.0.30 72.0 144.0 216.0 288.0 360.0 432.0 504.0 576.0 648.0 720.0.50 120.0 240.0 360.0 480.0 600.0 720.0 840.0 960.0 1080.0 1200.01.00 240.0 480.0 720.0 960.0 1200.0 1440.0 1680.0 1920.0 2160.0 2400.0

Material Thickness (Inches) "R" "U"

Glass Fibre Batts 1 3.0 0.332.5 0.153.5 0.16 0.07

Cork 1 3.3 0.32 0.183 0.14 0.0755 0.076 0.068 0.049 0.0210 0.01

Sawdust 1 1.68 0.606 0.1

Wood 1 1.2 0.85Blackjoe 0.5 1.0 0.8Concrete 1 0.1 10.00

16

Section Three: TablesTable 1 - "U" Values of Various Insulations

* For temperature differences greater than 100°F, Btu/sq. ft. factor will be in direct proportion (e.g. for 120°F use factor for 60°F T.D. and multiply by 2).


Table 3 - Average Air Changes Per 24 Hours

Storage Rooms Below 32°F Storage Rooms Above 32°F

Volume Air Changes Volume Air Changes Volume Air Changes Volume Air ChangesCubic Feet Per 24 Hrs. Cubic Feet Per 24 Hrs. Cubic Feet Per 24 Hrs. Cubic Feet Per 24 Hrs.

250 30.0 6,000 5.2 250 38.0 8,000 5.5

300 26.5 8,000 4.5 300 34.5 10,000 4.9

400 23.5 10,000 4.0 400 29.5 15,000 3.9

500 20.0 15,000 2.8 500 26.0 20,000 3.5

600 17.5 20,000 2.5 600 23.0 25,O00 3.0

800 15.0 25,000 2.2 800 20.0 3O,000 2.7

1,000 13.5 30,000 2.0 1,000 17.5 4O,000 2.3

1,500 12.3 40,000 1.8 1,500 14.0 5O,000 2.0

2,000 11.9 50,000 1.5 2,000 12.0 75,000 1.6

3,000 7.8 75,000 1.2 3,000 9.5 100,000 1.4

4,000 6.0 100,000 1.0 4,000 8.2

5,000 5.6 5,000 7.2

6,000 6.5

NOTE: For storage rooms with anterooms reduce values by 50%; for heavy usage rooms, increase values by 2. Compiled in part from ASHRAEHandbook of Fundamentals, 1989.

17


Table 4 - Heat Removed in Cooling Air to Storage Room Conditions (Btu per cu. ft.)

In Rooms Below 32°FStorage Temperature of Outside Air °FRoomTemp 40 50 70 90

°F Relative Humidity, Percent70 80 70 80 50 60 50 60

30 0.21 0.26 0.55 0.62 1.09 1.21 2.05 2.3125 0.37 0.43 0.71 0.78 1.19 1.36 2.20 2.4620 0.52 0.58 0.86 0.93 1.39 1.51 2.33 2.6015 0.66 0.72 1.00 1.07 1.50 1.63 2.46 2.7210 0.80 0.85 1.13 1.20 1.63 1.75 2.58 2.845 0.92 0.97 1.25 1.32 1.74 1.87 2.69 2.950 1.04 1.09 1.36 1.43 1.80 1.98 2 80 3.06-5 1.15 1.20 1.47 1.55 1.92 2.05 2.90 3.16-10 1.26 1.31 1.58 1.65 2.05 2.18 3.00 3.26-15 1.37 1.42 1.69 1.76 2.15 2.28 3.10 3.36-20 1.47 1.52 1.79 1.86 2.25 2.38 3.19 3.46-25 1.57 1.62 1.89 1.96 2.35 2.47 3.29 3.55-30 1.67 1.72 1.99 2.06 2.44 2.56 3.38 3.64

In Rooms Above 32°FStorage Temperature of Outside Air °FRoomTemp 70 85 90 95

°F Relative Humidity, Percent50 60 50 60 50 60 50 60

65 - - 0.32 0.52 0.58 0.81 0.85 1.1260 .18 .18 0.58 0.78 0.83 1.06 1.10 1.3755 .27 .27 0.80 1.00 1.05 1.28 1.32 1.5950 .39 .51 1.01 1.21 1.26 1.49 1.53 1.7945 .59 .72 1.20 1.40 1.45 1.68 1.71 1.9840 .76 .89 1.37 1.57 1.62 1.85 1.88 2.1535 .93 1.06 1.54 1.74 1.78 2.01 2.04 2.3130 1.08 1.21 1.78 2.01 2.05 2.31 2.33 2.64

Compiled in part from ASHRAE Handbook of Fundamentals,1989.

18


Table 5 - Requirements and Properties of Perishable ProductsSpecific SpecificHeat Heat

Storage Relative Approximate Water Highest above below LatentTemperature, Humidity, Storage Content. Freezing, 32°F 32°F Heat

Commodity °F % Life % °F Btu/lb °F Btu/lb °F Btu/lbVegetables

ArtichokesGlobe 32 95 - 100 2 weeks 84 29.9 0.87 0.45 120Jerusalem 32 90 - 95 5 months 80 27.5 0.83 0.44 114

Asparagus 32 - 36 95 - 100 2 - 3 weeks 93 30.9 0.94 0.48 133Beans

Snap or Green 40 - 45 95 7 - 10 days 89 30.7 0.91 0.47 127Lima 37 - 40 95 3 - 5 days 67 30.0 0.73 0.40 94Dried 50 70 6 - 8 months 11 0.32 0.23

BeetsRoots 32 95 - 100 4 - 6 months 88 30.4 0.90 0.46 126Bunch 32 95 10 - 14 days 31.3

Broccoli 32 95 - 100 10 - 14 days 90 30.9 0.92 0.47 130Brussels Sprouts 32 95 - 100 3 - 5 weeks 85 30.6 0.88 0.46 122Cabbage, late 32 98 - 100 5 - 6 months 92 30.4 0.94 0.47 132Carrots

Topped-immature 32 98 - 100 4 - 6 weeks 88 29.5 0.90 0.46 126Topped-mature 32 98 - 100 5 - 9 months 88 29.5 0.90 0.46 126

Cauliflower 32 95 2 - 4 weeks 92 30.6 0.93 0.47 132Celeriac 32 95 - 100 3 - 4 months 88 30.4 0.91 0.46 126Celery 32 98 - 100 1 - 2 months 94 31.1 0.95 0.48 135Collards 32 95 10 - 14 days 87 30.6 0.90 0.46 125Corn, Sweet 32 95 - 98 4 - 8 days 74 30.9 0.79 0.42 106Cucumbers 50 - 55 95 10 - 14 days 96 31.1 0.97 0.49 137Eggplant 46 - 54 90 - 95 7 - 10 days 93 30.6 0.94 0.48 133Endive (Escarole) 32 95 - 100 2 - 3 weeks 93 31.9 0.94 0.48 133Frozen Vegetables -10 - 0 6 - 12 monthsGarlic, dry 32 65 - 70 6 - 7 months 61 30.6 0.69 0.40 89Greens, leafy 32 95 - 100 10 - 14 days 93 31.5 0.94 0.48 133Horseradish 30 - 32 95 - 100 10 - 12 months 75 28.7 0.78 0.42 104Kale 32 95 3 - 4 weeks 87 31.1 0.89 0.46 125Kohlrabi 32 95 2 - 4 weeks 90 30.2 0.92 0.47 129Leeks, green 32 95 1 - 3 months 85 30.7 0.88 0.46 122Lettuce, head 32 - 34 95 - 100 2 - 3 weeks 95 31.7 0.96 0.48 136Mushrooms 32 95 3 - 4 days 91 30.4 0.93 0.47 130Okra 45 - 55 90 - 95 7 - 10 days 90 28.7 0.92 0.46 129Onions

Green 32 95 - 100 3 - 4 weeks 89 30.4 0.91 0.47 127Dry, & onion sets 32 65 - 75 1 - 8 months 88 30.6 0.90 0.46 126

Parsley 32 95 - 100 1 - 2 months 85 30.0 0.88 0.45 122Parsnips 32 98 - 100 4 - 6 months 79 30.4 0.84 0.44 112Peas

Green 32 95 1 - 3 weeks 74 30.9 0.79 0.42 106Dried 50 70 6 - 8 months 12 0.30 0.24

PeppersDried 32 - 50 60 - 70 6 months 12 0.30 0.24 17Sweet 45 - 50 90 - 95 2 - 3 weeks 92 30.7 0.94 0.47 132

PotatoesEarly 50 - 55 90 81 30.9 0.85 0.44 116Main crop 38 - 50 90 - 95 5 - 8 months 78 30.9 0.82 0.43 111Sweet 55 - 61 85 - 90 4 - 7 months 69 29.7 0.76 0.41 99

Pumpkins 50 - 55 50 - 75 2 - 3 months 91 30.6 0.92 0.47 130Radishes

Spring 32 95 3 - 4 weeks 95 30.7 0.95 0.48 134Winter 32 95 - 100 2 - 4 months 95 30.7 0.95 0.48 134

Rhubarb 32 95 2 - 4 weeks 95 30.3 0.95 0.48 134Rutabagas 32 98 - 100 4 - 6 months 89 30.0 0.91 0.47 127Salsify 32 98 - 100 2 - 4 months 79 30.0 0.83 0.44 113Seed, vegetable 32 - 50 50 - 65 10 - 12 months 7 - 15 0.29 0.23 16Spinach 32 95 - 98 10 - 14 days 93 31.5 0.94 0.48 133

19


20

Table 5 - Requirements and Properties of Perishable Products (continued)Specific SpecificHeat Heat


Commodity °F % Life % °F Btu/lb °F Btu/lb °F Btu/lbVegetables continued

SquashAcorn 45 - 50 70 - 75 5 - 8 weeks 30.6Summer 41 - 50 95 5 - 14 days 94 31.1 0.95 0.48- 135Winter 50 - 55 50 - 75 4 - 6 months 85 30.6 0.88 0.45 122

TomatoesMature green 55 - 70 90 - 95 1 - 3 weeks 93 31.0 0.94 0.48 133Firm, ripe 45 - 50 90 - 95 4 - 7 days 94 31.1 0.95 0.48 134

TurnipsRoots 32 95 4 - 5 months 92 30.0 0.93 0.47 132Greens 32 95 10 - 14 days 90 31.6 0.92 0.47 129

Watercress 32 95 3 - 4 days 93 31.4 0.94 0.48 133Yams 61 85 - 90 3 - 6 months 74 0.79 0.42 105

Fruits and MelonsApples 30 - 40 90 - 95 3 - 8 months 84 30.0 0.87 0.45 121Apples, dried 32 - 41 55 - 60 5 - 8 months 24 0.42 0.27Apricots 32 90 - 95 1 - 2 weeks 85 30.0 0.88 0.46 122Avocados 40 - 55 85 - 90 2 - 4 weeks 65 31.5 0.72 0.40 94Bananas 85 - 95 75 30.6 0.80 0.42 108Blackberries 31 - 32 90 - 95 3 days 85 30.6 0.88 0.46 122Blueberries 31 - 32 90 - 95 2 weeks 82 29.7 0.86 0.45 118Cantaloupes 36 - 40 95 5 - 15 days 92 29.8 0.93 0.48 132Cherries

Sour 31 - 32 90 - 95 3 - 7 days 84 29.0 0.87 0.45 121Sweet 30 - 31 90 - 95 2 - 3 weeks 80 28.8 0.84 0.44 114

Casaba Melons 45 - 50 85 - 95 4 - 6 weeks 93 30.0 0.94 0.48 133Cranberries 36 - 40 90 - 95 2 - 4 months 87 30.4 0.90 0.46 124Currants 31 - 32 90 - 95 10 - 14 days 85 30.2 0.88 0.45 122Dates, cured 0 - 32 75 or less 6 - 12 months 20 3.7 0.36 0.26 29Dewberries 31 - 32 90 - 95 3 days 85 29.7 0.88 0.45 122

FigsDried 32 - 40 50 - 60 9 - 12 months 23 0.39 0.27 34

Fresh 31 - 32 85 - 90 7 - 10 days 78 27.6 0.82 0A3 112Frozen fruits -10 - 0 90 - 95 6 - 12 monthsGooseberries 31 - 32 90 - 95 2 - 4 weeks 89 30.0 0.90 0.46 127Grapefruit 50 - 60 85 - 90 6 - 10 weeks 89 30.0 0.90 0.46 127Grapes

American 31 - 32 85 - 90 2 - 8 weeks 82 29.7 0.86 0.45 118Vinifera 31 90 - 95 3-6months 82 28.1 0.86 0.45 118

Guavas 41 - 50 90 2 - 3 weeks 83 0.86 0.45 119Honeydew Melons 45 - 50 90 - 95 3 - 4 weeks 93 30.4 0.94 0.48 133Lemons 32 - 50 85 - 90 1 - 6 months 89 29.4 0.91 0.46 127Limes 48 - 50 85 - 90 6 - 8 weeks 86 29.1 0.89 0.46 123Mangoes 55 85 - 90 2 - 3 weeks 81 30.4 0.85 0.44 117Nectarines 31 - 32 90 2 - 4 weeks 82 30.4 0.86 0.44 118Olives, fresh 41 - 50 85 - 90 4 - 6 weeks 75 29.4 0.80 0.42 108Oranges 32 - 48 85 - 90 3 - 12 weeks 87 30.6 0.90 0.46 124Papayas 45 85 - 90 1 - 3 weeks 91 30.6 0.82 0.47 130Peaches 31 - 32 90 - 95 2 - 4 weeks 89 30.4 0.91 0.46 127Peaches, dried 32 - 41 55 - 60 5 - 8 months 25 0.43 0.28Pears 29 - 31 90 - 95 2 - 7 months 83 29.2 0.86 0.45 118Persian Melons 45 - 50 90 - 95 2 weeks 93 30.6 0.94 0.48 133Persimmons 30 90 3 - 4 months 78 28.1 0.84 0.48 112Pineapples, ripe 45 85 - 90 2 - 4 weeks 85 30.2 0.88 0.45 122Plums 31 - 32 90 - 95 2 - 4 weeks 86 30.6 0.88 0.45 123Pomegranates 41 90 - 95 2 - 3 months 82 26.6 0.86 0.44 118Prunes

Fresh 31 - 32 90 - 95 2 - 4 weeks 86 30.5 0.88 0.45 123Dried 32 - 41 55 - 60 5 - 8 months 28 0.46 0.28


21



Commodity °F % Life % °F Btu/lb °F Btu/lb °F Btu/lbFruits & Melons continued

Quinces 31 - 32 90 2 - 3 months 85 28.4 0.88 0.45 122Raisins 18 0.38 0.25Raspberries

Black 31 - 32 90 - 95 2 - 3 days 81 30.0 0.84 0.44 117Red 31 - 32 90 - 95 2 - 3 days 84 30.9 0.87 0.45 120

Strawberries 31 - 32 90 - 95 5 - 7 days 90 30.6 0.92 0.47 129Tangerines 40 90 - 95 2 - 4 weeks 87 30.0 0.90 0.46 122Watermelons 50 - 60 90 2 - 3 weeks 93 31.3 0.97 0.48 133

Seafood (Fish)Haddock,Cod.Perch 31-34 95-100 12 days 81 28 0.85 0.44 117Hake, Whiting 32 - 34 95 - 100 10 days 81 28 0.85 0.44 117Halibut 31 - 34 95 - 100 18 days 75 28 0.80 0.42 107Herring

Kippered 32 - 36 80 - 90 10 days 61 28 0.70 0.38 87Smoked 32 - 36 80 - 90 10 days 64 28 0.72 0.39 92

Mackerel 32 - 34 95 - 100 6 - 8 days 65 28 0.73 0.40 93Menhaden 34 - 41 95 - 100 4 - 5 days 62 28 0.71 0.39 89Salmon 31 - 34 95 - 100 18 days 64 28 0.72 0.39 92Tuna 32 - 36 95 - 100 14 days 70 28 0.77 0.40 100Frozen Fish -20 to -4 90 - 95 6 - 12 months

Seafood (Shellfish)Scallop meat 32-34 95-100 12days 80 28 0.84 0.44 114Shrimp 31 - 34 95 - 100 12 - 14 days 76 28 0.81 0.43 109Lobster.American 41-50 In sea water Indefinitely 79 28 0.83 0.44 113Oysters, Clams

(meat & liquid) 32 - 36 100 5 - 8 days 87 28 0.89 0.46 125Oyster in shell 41-50 95-100 5days 80 27 0.84 0.44 115Frozen shellfish -20 to -4 90 - 95 3 - 8 months

Meat (Beef)Beef, fresh, average 32 - 34 88 - 92 1 - 6 weeks 62 - 77 28 - 29 0.70 - 0.84 0.39 - 0.43 89 - 110Beef carcass

Choice, 60% lean 32 - 39 85 - 90 1 - 3 weeks 49 29 0.61 0.35 70Prime, 54% lean 32 - 34 85 1 - 3 weeks 45 28 0.58 0.34 64

Sirloin cut (choice) 32 - 34 85 1 - 3 weeks 56 0.66 0.37 80Round cut (choice) 32 - 34 85 1 - 3 weeks 67 0.50 0.40 96Dried, chipped 50 - 59 15 6 - 8 weeks 48 0.60 0.34 69Liver 32 90 5 days 70 29 0.77 0.41 100Veal, 81% lean 32 - 34 90 1 - 7 days 66 0.74 0.40 94Beef, frozen - 10 - 0 90 - 95 6 - 12 months

Meat (Pork)Pork, fresh average 32 - 34 85 - 90 3 - 7 days 32 - 44 28 - 29 0.48 - 0.57 0.30 - 0.33 46 - 63Carcass, 47% lean 32 - 34 85 - 90 3 - 5 days 37 0.52 0.31 53Bellies, 35% lean 32 - 34 85 3 - 5 days 30 0.47 0.29 43Backfat, 100% fat 32 - 34 85 3 - 7 days 8 0.30 0.22Shoulder, 67% lean 32 - 34 85 3 - 5 days 49 28 0.61 0.35 70Pork, frozen - 10 - 0 90 - 95 4 - 8 monthsHam

74% lean 32 - 34 80 - 85 3 - 5 days 56 29 0.66 0.37 80Light cure 37 - 41 80 - 85 1 - 2 weeks 57 0.67 0.37 82Country cure 50 - 59 65 - 70 3 - 5 months 42 0.56 0.33 60Frozen - 10 - 0 90 - 95 6 - 8 months

BaconMedium fat class 37 - 41 80 - 85 2 - 3 weeks 19 0.38 0.26 27Cured, farm style 61 - 64 85 4 - 6 months 13 - 20 0.34 - 0.39 0.24 - 0.26 19 - 29


22



Commodity °F % Life % °F Btu/lb °F Btu/lb °F Btu/lbMeat (Pork) continued

Bacon continuedCured, packer style 34 - 39 85 2 - 6 weeks

Frozen - 10 - 0 90 - 95 2 - 4 monthSausageLinks or bulk 32 - 34 85 1 - 7 days 38 0.53 0.31 54Country, smoked 32 85 1 - 3 weeks 50 25 0.62 0.35 72

Frankfurters, average 32 85 1 - 3 weeks 56 29 0.66 0.37 80Polish style 32 85 1 - 3 weeks 54 0.65 0.36 77

Meat (Lamb)Fresh, average 32 - 34 85 - 90 5 - 12 days 60 - 70 28 - 29 0.69 - 0.77 0.38 - 0.41 86 - 100Choice, 67% 1lean 32 85 5 - 12 days 61 28 0.70 0.38 87Leg, choice, 83% 1lean 32 85 5 - 12 days 65 0.73 0.40 93Frozen - 10 - 0 90 - 95 8 - 12 months

Meat (Poultry)Poultry, fresh, average 28 - 32 95 - 100 1 - 4 weeks 74 27 0.80 0.42 106Chicken, all classes 28 - 32 95 - 100 1 - 4 weeks 74 27 0.80 0.42 106Turkey, all classes 28 - 32 95 - 100 1 - 4 weeks 64 27 0.72 0.39 92Duck 28 - 32 95 - 100 1 - 4 weeks 69 27 0.76 0.41 99Poultry, frozen - 10 - 0 90 - 95 12 months

Meat (Miscellaneous)Rabbits, fresh 32 - 34 90 - 95 1 - 5 days 68 0.75 0.40 97

Dairy ProductsButter 32 75 - 85 1 month 16 -4 - 31 0.36 0.25 23Butter, frozen - 10 70 - 85 12 monthsCheese, Cheddar

long storage 32 - 34 65 12 months 37 8 0.52 0.31 53short storage 40 65 6 months 37 8 0.52 0.31 53processed 40 65 12 months 39 19 0.50 0.31 56grated 40 65 12 months 31 0.45 0.29 44

Ice cream, 10% fat -20 to -15 3 - 23 months 63 21 0.70 0.39 86Milk

Whole, pasteurizedGrade A 32 - 34 2 - 4 months 87 31 0.93 0.46 125Dried, whole 70 Low 6 - 9 months 2 0.26 0.21 28Dried, nonfat 45 - 70 Low 16 months 3 0.26 0.21 4Evaporated 40 24 months 74 29.5 0.79 0.42 106Evaporatedunsweetened 70 12 months 74 29.5 0.79 0.42 106Condensedsweetened 40 15 months 27 5 0.42 0.28 40

Whey, dried 70 Low 12 months 5 0.28 0.22 7Eggs

EggsShell 29 - 32 80 - 85 5 - 6 months 66 28 0.73 0.40 96Shell, farm cooler 50 - 55 70 - 75 2 - 3 weeks 66 28 0.73 0.40 96

FrozenWhole 0 1 year plus 74 0.80 0.42 106Yolk 0 1 year plus 55 0.65 0.36 79White 0 1 year plus 88 0.90 0.46 126Whole egg solids 35 - 40 Low 6 - 12 months 2 - 4 0.22 0.21 4

Yolk solids 35 - 40 Low 6 - 12 months 3 - 5 0.23 0.21 6


23



Commodity °F % Life % °F Btu/lb °F Btu/lb °F Btu/lbEggs continued

Flake albumen solids Low 1 year plus 12 - 16 0.31 0.24 20Dry spray albumen

solids Low 1 year plus 5 - 8 0.26 0.22 11Candy

Milk chocolate 0 - 34 40 6 - 12 months 1 0.25 0.20 1Peanut brittle 0 - 34 40 1.5 - 6 months 2 0.26 0.21 3Fudge 0 - 34 65 5 - 12 months 10 0.32 0.23 14Marshmallows 0 - 34 65 3 - 9 months 17 0.37 0.25 24

MiscellaneousAlfalfa meal 0 70 - 75 1 year plusBeer

Keg 35 - 40 3 - 8 weeks 90 28 0.92 0.47 129Bottles and cans 35 - 40 65 or below 3 - 6 months 90

Bread 0 3 - 13 weeks 32 - 37 0.70 0.34 46 - 53Canned goods 32 - 60 70 or lower 1 yearCocoa 32 - 40 50 - 70 1 year plusCoconuts 32 - 35 80 - 85 1 - 2 months 47 30.4 0.58 0.34 67Coffee, green 35 - 37 80 - 85 2 - 4 months 10 - 15 0.32 - 0.35 0.23 - 0.24 14 - 21Fur and fabrics 34 - 40 45 - 55 Several YearsHoney 50 1 year plus 17 0.35 0.26 26Hops 28 - 32 50 - 60 Several monthsLard (without 45 90-95 4-8 months 0antioxidant) 0 90 - 95 12 - 14 months 0Maple syrup 33 0.48 0.31 51Nuts 32 - 50 65 - 75 8 - 12 months 3 - 6 0.22 - 0.25 0.21 - 0.22 4 - 8Oil,vegetable, salad 70 1 year plus 0Oleomargarine 35 60 - 70 1 year plus 16 0.32 0.25 22Orange juice 30 - 35 3 - 6 weeks 89 0.91 0.47 127Popcorn, unpopped 32 - 40 85 4 - 6 weeks 10 0.31 0.24 19Yeast, baker's compressed 31 - 32 71 0.77 0.41 102Tobacco

Hogshead 50 - 65 50 - 65 1 yearBales 35 - 40 70 - 85 1 - 2 yearsCigarettes 35 - 46 50 - 55 6 monthsCigars 35 - 50 60 - 65 2 months

Compiled in part from ASHRAE Refrigeration Handbook,1990.


Table 6 - Approximate Heat of Respiration Rates at Temperature IndicatedBtu/Pound/24 Hours Btu/Pound/24 Hours

Product 32°F 40°F 60°F Product 32°F 40°F 60°F

Apples 0.45 0.8 2.05 Melons - Honeydews - 0.5 1.4

Asparagus 4.70 9.0 18.5 Mushrooms 3.1 - -

Beans - Green 3.15 5.15 19.1 Okra - 6.0 15.8

Beans - Lima 1.35 2.6 12.2 Onions 0.45 0.5 1.2

Beets 1.35 1.75 3.6 Onions - Green 1.8 4.9 9.0

Blueberries 0.85 - - Oranges 0.35 0.7 2.2

Broccoli 3.75 7.0 21.0 Peaches 0.6 0.85 4.2

Brussels Sprouts 2.9 4.4 10.1 Pears 0.4 0.85 5.4

Cabbage 0.6 0.85 2.05 Peas 4.2 7.4 21.0

Carrots 1.05 1.75 4.05 Peppers - Green 1.35 2.4 4.3

Cauliflower 1.95 2.25 5.05 Peppers - Sweet 1.35 2.4 4.3

Celery 0.8 1.2 4.1 Plums 0.3 0.6 1.3

Cherries 0.75 1.4 6.0 Potatoes - Immature - 1.3 2.4

Corn 4.65 6.0 19.2 Potatoes - Mature - 0.8 1.0

Cranberries 0.33 0.45 - Raspberries 2.4 3.8 10.1

Cucumbers 0.28 - - Spinach 2.3 5.1 18.5

Grapefruit 0.35 0.50 1.55 Strawberries 1.6 2.7 9.0

Grapes 0.3 0.6 1.75 Sweet Potatoes 0.9 1.25 2.7

Lemons 0.35 0.65 1.8 Tomatoes - Green 0.3 0.55 3.1

Lettuce - Head 1.15 1.35 4.0 Tomatoes - Ripe 0.5 0.65 2.8

Lettuce - Leaf 2.2 3.2 7.2 Turnips 0.95 1.1 2.65

Melons - Cantaloupes 0.65 1.0 4.3

Compiled in part from ASHRAE Handbook of Fundamentals,1989.

24


Table 7 - Heat Equivalent of Electric Motors Btu/Hp/Hr

Connected Motor Losses ConnectedMotor Load in Outside Load Outside

Hp Refrigerated Space1 Refrigerated Space2 Refrigerated Space3

Btu/Hr Watts Btu/Hr Watts Btu/Hr Watts

1/8 - 1/2 4,250 1,243 2,545 744 1,700 497

1/2 - 3 3,700 1,081 2,545 744 1,150 337

3 - 20 2,950 863 2,545 744 400 117

1. For use when both useful output and motor losses are dissipated within refrigerated 3. For use when motor heat losses are dissipated within refrigerated space and useful workspace, motors driving fans for forced circulation unit coolers. expended outside of refrigerated space; motor in refrigerated space driving pump or fan

2. For use when motor losses are dissipated outside refrigerated space and useful work of located outside of space.motor is expended within refrigerated space; pump on a circulating brine or chilled water system,fan motor outside refrigerated space driving fan circulating air within refrigerated space.

Table 8 - Heat Equivalent of OccupancyCooler Temperature °F Heat Equivalent/Person Btu/Hr.

50 720

40 840

30 950

20 1,050

10 1,200

0 1,300

-10 1,400

25

Table 9 - Summer Outdoor Design Data(Design dry bulb and wet bulb temperature represents temperature equalled or exceeded during 1% of hours during the four summer months.)

Dr Bulb Wet Bulb Dr Bulb Wet BulbLocation °F °F Location °F °F

Alabama ColoradoBirmingham 97 79 Denver 92 65Mobile 96 80 Connecticut

Alaska Hartford 90 77Fairbanks 82 64 DelawareJuneau 75 66 Wilmington 93 79

Arizona D.C.Phoenix 108 77 Washington 94 78Tucson 105 74 Florida

Arkansas Jacksonville 96 80Fort Smith 101 79 Miami 92 80Little Rock 99 80 Tampa 92 81

California GeorgiaBakersfield 103 72 Atlanta 95 78Blythe 111 78 Savannah 96 81Los Angeles 94 72 HawaiiSan Francisco 80 64 Honolulu 87 75Sacramento 100 72 Idaho

Boise 96 68


26

Table 9 - Summer Outdoor Design Data continued(Design dry bulb and wet bulb temperature represents temperature equalled or exceeded during 1% of hours during the four summer months.)

Dr Bulb Wet Bulb Dr Bulb Wet BulbLocation °F °F Location °F °F

Illinois OhioChicago 94 78 Cincinnati 94 78Springfield 95 79 Cleveland 91 76

Indiana OklahomaFort Wayne 93 77 Tulsa 102 79Indianapolis 93 78 Oregon

Iowa Pendleton 97 66Des Moines 95 79 Portland 91 69Sioux City 96 79 Pennsylvania

Kansas Philadelphia 93 78Dodge City 99 74 Pittsburgh 90 75Wichita 102 77 Rhode Island

Kentucky Providence 89 76Lexington 94 78 South CarolinaLouisville 96 79 Charleston 94 81

Louisiana South DakotaNew Orleans 93 81 Sioux Falls 95 77Shreveport 99 81 Tennessee

Maine Memphis 98 80Portland 88 75 Nashville 97 79

Maryland TexasBaltimore 94 79 Dallas 101 79

Massachusetts El Paso 100 70Boston 91 76 Galveston 91 82Worcester 89 75 Houston 96 80

Michigan UtahDetroit 92 76 Salt Lake City 97 67Grand Rapids 91 76 Vermont

Minnesota Burlington 88 74Duluth 85 73 VirginiaMinnesota 92 77 Richmond 96 79

Mississippi Roanoke 94 76Biloxi 93 82 WashingtonJackson 98 79 Seattle 82 67

Missouri Spokane 93 66Kansas City 100 79 Yakima 94 69St. Louis 96 79 West Virginia

Montana Charleston 92 76Billings 94 68 WisconsinHelena 90 65 Milwaukee 90 77

Nebraska WyomingOmaha 97 79 Cheyenne 89 63

Nevada CanadaLas Vegas 108 72 AlbertaReno 95 64 Calgary 87 66

New Hampshire British ColumbiaConcord 91 75 Vancouver 80 68

New Jersey ManitobaNewark 94 77 Winnipeg 90 75Trenton 92 78 New Brunswick

New Mexico St. John 81 71Albuquerque 96 66 NewfoundlandSanta Fe 90 65 Gander 85 69

New York Nova ScotiaAlbany 91 76 Halifax 83 69Buffalo 88 75 OntarioNew York 93 77 Toronto 90 77

North Carolina QuebecCharlotte 96 78 Montreal 88 76

North Dakota SaskatchewanBismark 95 74 Regina 92 73

YukonWhitehorse 78 62


Table 10 - Operating Conditions for Storage

Temp. Humidity Operating Designed Running Time°F T.D. °F For Unit

35 - 40 55% - 65% 20 - 25 18 hours

Table 11 - Insulation Requirements for Storage Rooms

Storage Temperature Desirable Insulation°F U Factor

-50 to -25 0.01-25 to 0 0.04O to 25 0.0625 to 40 0.075

40 and up 0.1

Table 12 - Suggested Freezer Temperatures °F

Bread 0 Vegetables -10

Candy 0 Beef -10

Ice Cream -15 Lamb -10Butter O to -10 Pork -10Eggs O or lower Veal -10Fish -10 Poultry -20

Shellfish -20

27

Thank You!The Replacement Components Division (RCD) of CarrierCorporation thanks you for considering Totaline refrigerationproducts. These products are engineered and manufacturedwith the utmost in quality control. RCD is ready to supportyour installation and all other needs with our full range ofTotaline Service Parts. Thanks again!

Manufacturer reserves the right to discontinue, or change at any time, specifications or designs and

prices without notice and without incurring obligations.

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