Dual FuelDual Fuel+

What will you know?What will you know?

► What are Hybrid Systems?What are Hybrid Systems?► What is Balance Point?What is Balance Point?► What is Power Consumption?What is Power Consumption?► What is Coefficient of What is Coefficient of

Performance?Performance?► What Controls?What Controls?► How to sell Hybrid Systems!How to sell Hybrid Systems!

What will you be able What will you be able to do?to do?

► Explain and configure Hybrid Explain and configure Hybrid SystemsSystems

► Determine Balance PointsDetermine Balance Points► Determine COPsDetermine COPs► Estimate Power ConsumptionEstimate Power Consumption► Sell Hybrid SystemsSell Hybrid Systems

What are you fixin’ to What are you fixin’ to do?do?

► Use Perf. Data and Program to Use Perf. Data and Program to determine Balance Pointdetermine Balance Point

► Use Perf. Data and Program to Use Perf. Data and Program to determine COPsdetermine COPs

► Complete Power Consumption Complete Power Consumption pagespages

► Practice the “story”Practice the “story”► GET TO WORK!!!GET TO WORK!!!

Furnace OperationFurnace Operation► Heat Loss = load in Heat Loss = load in

winterwinter► Gas, Propane, Oil Gas, Propane, Oil

furnace replaces furnace replaces heat by fuel heat by fuel combustioncombustion

► Output/capacity Output/capacity constant regardless constant regardless of OD Temp.of OD Temp.

Heat Pump OperationHeat Pump Operation► Heat Loss = load in winterHeat Loss = load in winter► Heat Pump replaces heat Heat Pump replaces heat

by transferring heat from by transferring heat from outsideoutside

► Output/capacity of HP Output/capacity of HP reduces as OD Temp. reduces as OD Temp. dropsdrops

► Air Conditioner in Air Conditioner in Reverse!Reverse!

Air Conditioner Air Conditioner OperationOperation

Evaporator Coil absorbs heat from the ID air as liquid

refrigerant evaporates

Condenser Coil releases heat into

the OD air as refrigerant gas condenses into

liquid

Heat Pump OperationHeat Pump Operation

Evaporator Coil absorbs heat from

the OD air as liquid refrigerant

evaporates

Condenser Coil releases heat into

the ID air as refrigerant gas condenses into

liquid

Heat Pump CapacityHeat Pump Capacity► As the OD Temperature drops, the As the OD Temperature drops, the

heating capacity of a heat pump heating capacity of a heat pump drops.drops.

Heat Pump Defrost Heat Pump Defrost CyclesCycles

► Defrost Cycles are factored into Defrost Cycles are factored into heat pump performance data.heat pump performance data.

Manual J – Residential Load Manual J – Residential Load Calculation (Version-7)Calculation (Version-7)

► ““The design heat loss must be calculated for The design heat loss must be calculated for the winter outdoor design temperature. the winter outdoor design temperature. Because the Because the maximummaximum heat loss occurs heat loss occurs during the early morning hours, before sun during the early morning hours, before sun rise and at a time of occupant inactivity, the rise and at a time of occupant inactivity, the heat gains due to solar radiation and internal heat gains due to solar radiation and internal heat gains are heat gains are notnot considered in the heat loss considered in the heat loss calculation.”calculation.”

► The furnace/heat pump is selected for the The furnace/heat pump is selected for the coldest day of the year!coldest day of the year!

► What about the other days???What about the other days???

Heat Loss = LinearHeat Loss = Linear► As the OD Temperature DROPS, As the OD Temperature DROPS,

the heat loss INCREASES and the heat loss INCREASES and vice vice versaversa!!

Balance PointBalance Point► The lowest OD Temperature at The lowest OD Temperature at

which the heat pump can supply which the heat pump can supply 100% of the heating required for 100% of the heating required for the space.the space.

Manual J: Version 7Manual J: Version 7► ““The design heat loss must be The design heat loss must be

calculated for the winter outdoor design calculated for the winter outdoor design temperature. Because the temperature. Because the maximummaximum heat loss occurs during the early heat loss occurs during the early morning hours, before sun rise and at a morning hours, before sun rise and at a time of occupant inactivity, the heat time of occupant inactivity, the heat gains due to solar radiation and internal gains due to solar radiation and internal heat gains are heat gains are notnot considered in the considered in the heat loss calculation.”heat loss calculation.”

► The Balance Point might be The Balance Point might be LOWERLOWER than you think!than you think!

Power ConsumptionPower Consumption

► Heat Loss in BtusHeat Loss in Btus► Calculate cost to replace Calculate cost to replace

Heat Loss in Btus - $$$Heat Loss in Btus - $$$► Need weather dataNeed weather data► Need efficiency of Need efficiency of

equipmentequipment► Need Btus of heat per unit Need Btus of heat per unit

of fuelof fuel► Need “Correction Factor"Need “Correction Factor" $$

Weather DataWeather Data“Bin Data”“Bin Data”

Equipment EfficiencyEquipment Efficiency► AFUE for FurnacesAFUE for Furnaces

► 80% or 90% Gas Furnace80% or 90% Gas Furnace► 80% Oil Furnace80% Oil Furnace

► Coefficient of Performance for Heat Coefficient of Performance for Heat Pumps – COP = (efficiency at a Pumps – COP = (efficiency at a specific condition)specific condition)► will vary with OD Temperature!!!will vary with OD Temperature!!!

Btu Outputs for FuelsBtu Outputs for Fuels► Natural Gas = Natural Gas = 100,000100,000 Btu per “Therm.” Btu per “Therm.”

► (100 Cubic Feet of Gas - CCF’s)(100 Cubic Feet of Gas - CCF’s)

► Propane = Propane = 91,50091,500 Btu per Gallon Btu per Gallon

► Oil = Oil = 130,000130,000 Btu per Gallon Btu per Gallon

► ElectricElectric = = 3.4133.413 Btus per Watt Btus per Watt► 3,413 Btus per Kilowatt (Kw)3,413 Btus per Kilowatt (Kw)► ( Kw = 1,000 watts )( Kw = 1,000 watts )

Coefficient of Coefficient of PerformancePerformance

(efficiency at a specific condition)(efficiency at a specific condition)► 1 Watt = 3.413 Btus of heat1 Watt = 3.413 Btus of heat► 1 Kilowatt = 3,413 Btus of heat1 Kilowatt = 3,413 Btus of heat► Heat Pump Capacity & Heat Pump Heat Pump Capacity & Heat Pump

Power - KwPower - Kw► Performance DataPerformance Data► COP at the Balance PointCOP at the Balance Point

(Heat Pump Capacity / Heat Pump Power - Kw)

3,413

““Correction Factor”Correction Factor”► Correction Factor = adjustment applied to

the number of heating load hours, given the effects of OD temperatures on structures and how these effects are delayed or diminished because of daily temperature changes – in other words, for the house to experience the full load effect of 32F (BtuH heat loss), the OD temperature must remain this low for quite a few hours. Normal daily ranges vary, which throws our calculations into disarray.

► Recommend beginning with Recommend beginning with 70%70%

Furnace Power Furnace Power Consumption Consumption

VariablesVariables► Heat Loss - Load CalculationHeat Loss - Load Calculation► Heating Load Hours - Weather DataHeating Load Hours - Weather Data► Fuel cost per unit (therm/gallon) - $Fuel cost per unit (therm/gallon) - $► Correction FactorCorrection Factor► AFUEAFUE► Btus per unit of fuel (therm/gallon)Btus per unit of fuel (therm/gallon)

► Methods from Manual J: Version 7 (Appendix A-3)Methods from Manual J: Version 7 (Appendix A-3)

Furnace Power Furnace Power ConsumptionConsumption

► Heat Loss - Load CalculationHeat Loss - Load Calculation► Heating Load Hours - Weather DataHeating Load Hours - Weather Data► Fuel cost per unit (therm/gallon) - $Fuel cost per unit (therm/gallon) - $► Correction FactorCorrection Factor► AFUEAFUE► Btus per unit of fuel (therm/gallon)Btus per unit of fuel (therm/gallon)

Heat Loss x Heating Load Hours x Fuel Cost-unit x Correction Factor

AFUE x Btu Per Unit of Fuel

Heat Pump Power Heat Pump Power ConsumptionConsumption

► Heat Loss - Load CalculationHeat Loss - Load Calculation► Heating Load Hours - Weather DataHeating Load Hours - Weather Data► Electric cost per Kw - $Electric cost per Kw - $► Correction FactorCorrection Factor► COPCOP► 1 Kw = 3,413 Btus 1 Kw = 3,413 Btus

Heat Loss x Heating Load Hours x Cost per Kw x Correction Factor

COP x 3,413

Furnace ExampleFurnace Example

► Heat Loss at 20°F = 43,651 Heat Loss at 20°F = 43,651 BtuHBtuH

► Heat Load Hours = 298Heat Load Hours = 298► $.80 per Therm. - Natural $.80 per Therm. - Natural

GasGas► 70% Correction Factor70% Correction Factor► XV80 Furnace - 80% AFUEXV80 Furnace - 80% AFUE

43,651 x 298 x .80 x .70

.80 x 100,000

$91 estimated cost of operation for this temperature range over a year period.

Heat Pump ExampleHeat Pump Example

► Heat Loss at 50°F = 21,825 Heat Loss at 50°F = 21,825 BtuHBtuH

► Heat Load Hours = 540Heat Load Hours = 540► $.07 per KwH$.07 per KwH► 70% Correction Factor70% Correction Factor► XL14i - COP = 2.8XL14i - COP = 2.8

21,825 x 540 x .07 x .70

2.8 x 3,413

$60 estimated cost of operation for this temperature range over a year period.

Heating Power Heating Power Consumption for Hybrid Consumption for Hybrid

SystemSystem

Power ConsumptionPower Consumption

Control is Control is KEY!KEY!

► 2 stage2 stage controls controls► Dual Fuel applications Dual Fuel applications

& considerations& considerations► No more TAYPLUS!No more TAYPLUS!

+ =

2 StageMild Winter Day

Furnace Winter DesignTemp. Furnace

2 Stage Operation =

+ =

Hybrid System

Mild Winter DaySystem Cold Winter Day

System

Hybrid Operation =

GET TO WORK!!!GET TO WORK!!!

Skills & Practice.Skills & Practice.

What will you be able What will you be able to do?to do?

► Explain and configure Hybrid SystemsExplain and configure Hybrid Systems► Determine Balance PointsDetermine Balance Points► Determine COPsDetermine COPs► Estimate Power ConsumptionEstimate Power Consumption► Sell Hybrid SystemsSell Hybrid Systems

► ***Laptop computer required******Laptop computer required***