What is the heating capacity in BTUH of a heat pump with a supply air temperature of 92°F and return air temperature of 70°F?

To determine the heating capacity of a heat pump, the temperature difference between the supply air and the return air is essential. The formula used to calculate heat capacity in BTU/H, based on the temperature difference and the airflow rate, is:

[ \text{Heating Capacity (BTUH)} = \text{CFM} \times 1.08 \times \Delta T ]

where CFM is the airflow rate in cubic feet per minute, and ( \Delta T ) is the temperature difference between the supply and return air.

In this case, the supply air temperature is 92°F and the return air temperature is 70°F, leading to a temperature difference of:

[ \Delta T = 92°F - 70°F = 22°F ]

If we assume a common airflow rate of 1,500 CFM, substituting the values into the heating capacity formula yields:

[ \text{Heating Capacity} = 1500 , \text{CFM} \times 1.08 \times 22°F ]

[ \text{Heating Capacity} = 1500 \times 1.08 \times 22 ]

[ \text{Heating Capacity} \approx 35,760