5.1.4

Method for calculating a SEER for units with two speed compressor, two compressor or cylinder unloading capable of varying the sensible to total capacity (S/T) ratio. Multi-speed compressor and twospeed compressor units capable of varying the sensible to total capacity ratio (S/T) shall have the seasonal energy efficiency ratio determined as described in section 5.1.3. For such units, the mode of operation selected to determine the steady-state capacities Q..*(95), Q..*(82), E.,*(95), E..*(82), and power inputs at each compressor speed k=1, k=2, for tests A and B is outlined in section 2.10.

5.1.5 Seasonal energy efficiency ratio for air-source units with triple-capacity compressors. (Reserved)

5.1.6 Seasonal energy efficiency ratio for air-source units with variable-speed compressors. For air-source units with variable-speed compressors, the seasonal energy efficiency ratio (SEER), shall be defined as follows:

82-67

E(T)=the electrical power input required by the unit to deliver capacity matching the building load at temperature Tj.

Q(T)=the capacity delivered by the unit matching the building load at temperature TJ.

EER (T})=the steady-state energy efficiency ratio at temperature T, and an intermediate speed at which the unit capacity matches the building load.

Before the steady-state intermediate speed energy efficiency ratio, EER (T1), can be calculated, the unit performance has to be evaluated at the

compressor speed (k=i) at which the intermediate speed test was conducted. The capacity of the unit at any temperature T, when the compressor operates at the intermédiate speed (k=i) may be determined by:

where

Q'(T)=Q'(87)+Mq(T;—87)

Q(87)=the capacity of the unit at 87°F determined by the intermediate cooling steadystate test.

T1 = temperature at which the unit, operating at the minimum compressor speed, delivers capacity equal to the building load (Q(T1)= BL(T1)), found by equating the capacity equation [(Q(T)] and building load equation [BL(T;)] in section 5.1.3 and solving for temperature.

=

T2 temperature at which the unit, operating at the maximum compressor speed, delivers capacity equal to the building load (Q2(T2)=BL(T2)), found by equating the capacity equation [(QT;)] and the building equation [BL(T;)] in section 5.1.3 and solving for temperature.

SS

EER (T1)=the steady state energy efficiency ratio at the minimum compressor speed at temperature T1.

EER (T2)= the steady state energy efficiency ratio at the maximum

compressor speed at temperature T2.

Ek (T1)=the electrical power input at the minimum compressor speed at temperature T1, calculated by the equation in section 5.1.3.

Ek (T2)=the electrical power input at the maximum compressor speed at temperature T2, calculated by the equation in section 5.1.3.

energy efficiency

ratio,

The EER''(T;), shall be calculated by the following equation:

Case III is the same as specified in 5.1.3.4. The quantities Q1(T) and Ek (T1) and ET,) shall be calculated by the equations prescribed in 5.1.3.

5.1.7. Seasonal energy efficiency ratio for split-type ductless systems. For splittype ductless systems, SEER shall be defined as specified in section 5.1.1 of this Appendix for each combination set of indoor coils to be used with a common outdoor unit.

5.2 Calculation of Heating Seasonal Performance Factors (HSPF) for AirSource Units.

The testing data and results required to calculate the heating seasonal performance factor (HSPF), in Btu's per watt-hr, shall include the following:

(i) Heating capacities (Btu/hr) from the indoor air enthalpy method for the High Temperature Tests, and the total heating done (Btu's) for the cyclic and frost accumulation tests.

Where the heating capacities Q..(47), Q..(62) and Q..(17) and the indoor air flow rate are calculated using the equations specified in section 3.8.1 and 7.4 of ASHRAE standard 37-78. The total heating done, Qoy.(47) and Q(DEF35) are calculated using the equations below.

Units not having an indoor fan as part of the model tested shall add 1250 Btu/hr per 1,000 SCFM of indoor air handled to the measured capacity to obtain the total heating capacity, Q..(17), Q..(47) or Q..(62), and add 365 watts per 1,000 SCFM of indoor air handled to the measured power to obtain the total power input, È....(17), È..(47), or È..(62), to the unit.

The coefficients of performance (COP) for the High Temperature Tests COP,,(62) or COP..(47), and Low Temperature Test, COP..(17), are calculated as the ratio of the heating capacity in Btu/hr to the product of 3.413 and the power inputs to the indoor fan in watts and the power inputs to the remaining equipment components (including all controls) in watts.

Units which do not have indoor air circulating fans furnished as part of the model shall have their total heating done (Qeye (47)) and energy used Eeyo (47) in one complete cycle adjusted for the effect of circulating indoor air equipment power. For units tested without an indoor fan as part of the model, Qoy.(47) shall be increased by a quantity of heat equal to the product of 1250 Btu/hr per 1,000 SCFM, the length of the on-period of the test cycle in hours, and the flow rate of indoor air circulated in units of 1,000 SCFM. The total energy usage, Ecye(47), shall be the sum of the energy usage required for air circulation during the test cycle and the energy used by the remaining equipment components (including all controls) during the test cycle. Units not having an indoor fan as part of the model tested, shall set the energy required for indoor air circulation equal to the quantity given by the product of 365 watts per 1000 SCFM, the length of the on-period of the test cycle in hours, and the rate of indoor air circulated in units of 1000 SCFM.

The cyclic coefficient of performance, COPeye (47) is calculated as the ratio of the total heating done (Qoye (47)) in Btu's to the product of 3.413 Btu/watt-hour and the total energy usage (Eye (47)) in watt hours.

The net heating capacity, QDEF (35) (Btu/hr), is the total net heating done over the test period (including any credit for the indoor fan heat) divided by the total length of the test period, in hours.

For units tested without indoor fans, the value determined for DEF (35) below shall be increased by a quantity of heat equal to the product of 1250 Btu/hr per 1000 SCFM, the length of time in hours during the Frost Accumulation Test that there was indoor air circulating, and the average flow rate of indoor air circulated in units of 1000 SCFM.

The total energy usage, EDEF (35) shall be the sum of the energy usage required for indoor-air circulation during the test period and the energy used by the remaining equipment components during the test period. Units not having an indoor fan as part of the model tested, shall set the energy required for indoor air circulation equal to the quantity given by the product of 365 watts per 1000 SCFM, the length of time in hours during the Frost Accumulation Test that there was indoor air circulating, and the average flow rate of indoor air circulated in units of 1000 SCFM.

The actual heating done during the Cyclic Test, Qoy.(47), shall be determined using the following equation:

where

V=the average of the air flow rate calculated at four or more time intervals throughout the heating phase of the test using the equation in section 7.4 of ASHRAE Standard 37-78.

C. Specific heat at constant pressure of air-water mixture per pound of dry air, (Btu/lb-°F). V-Specific volume of air-water mixture at the same dry-bulb temperature, humidity ratio, and pressure used in the determination of the indoor air flow rate (ft/lb).

W. Humidity ratio (1b/1b).

and г (hr.-°F), which is described by the equation:

60 XTXCXг

(3)

CD=

1-HLF

[V21× (1+W2)]

where

where

V-the flow rate during the on-period calculated in

accordance with section 7.4 of ASHRAE Standard 37-78 in CFM.

C.-Specific heat at constant pressure of air-water mixture per pound of dry air, (Btu/b-°F).

V-Specific volume of air-water mixture at the same dry-bulb temperature, humidity ratio, and pressure used in the determination of the indoor air flow rate (ft3/1b).

W. Humidity ratio (lb/lb).

and г (hr-°F), which is described by the equation:

Qeye (47) as defined above
Q..(47) as defined above

Duration of time (hours) for one complete
cycle consisting of one compressor "on" time
and one compressor "off" time.

For air-source units that are equipped with "demand defrost control systems", the value for HSPF, as determined above shall be multiplied by an enhancement factor Fdef to compensate for improved performance not measured in the Frost Accumulation Test. The factor, Fder depends on the number of defrost cycles in a 12-hour period and should be calculated as follows:

Fder=1+0.03*(1-(Ttest-90)/(Tmar-90))