Using manufacturer's

Using manufacturer's performance data, determine the water flow rate (GPM) and the heating capacity of the installation using the measured PD and the measured EWT.
e) Determine heating capacity by using the following formula: Btuh = TD x 1.1 x CFM TD =  temperature difference between supply air and return air 1.1 =  air properties constant CFM =  Cubic feet per minute air calculated, from funnel, temperature rise, or return air method
f) Verify that system capacity is + 10% of the equipment manufacturer's rating at the test conditions.
3) Check system cooling capacity as follows: (Major)
a) Allow system to operate for at least 15 minutes
b) Measure water pressure drop (PD) between water-in and water-out test plugs at heat pump. (Use same instrument to measure both to reduce error).
c) Measure entering water temperature at water-in test plug.
d) Using manufacturer's performance data, determine the water flow rate (GPM) and the cooling capacity of the installation using the measured PD and the measured EWT