Heat Pump Airflow Calculator
Airflow checks for a heat pump in both modes.
Enter your values
ⓘ Live results
Results
- Design airflow
- 1,200 CFM
- Heating airflow
- 1,260 CFM
- Aux heat rise
- 26.3 °F
- Supply temp with aux at 70°F return
- 96 °F
- Aux capacity
- 34,120 BTU/h
Quick answer
Heat pumps generally need 400 CFM per ton in cooling and slightly more in heating to keep supply temperatures comfortable.
CFM = tons x 400; strip rise = kW x 3412 / (1.08 x CFM)
How to use the Heat Pump Airflow Calculator
- 1Enter the system tonnage and target CFM per ton.
- 2Add the auxiliary strip heat capacity in kW.
- 3Verify the temperature rise with strips on is inside the air handler's listed range.
Worked example
Using the values the calculator loads with:
Inputs
- System size3 tons
- CFM per ton400 CFM/ton
- Auxiliary heat10 kW
Results
- Design airflow1,200 CFM
- Heating airflow1,260 CFM
- Aux heat rise26.3 °F
- Supply temp with aux at 70°F return96 °F
- Aux capacity34,120 BTU/h
Frequently asked questions
Why does heat pump air feel cool?
Supply air is typically 95-105°F, below body temperature, so it feels cool even while heating effectively.
More airflow in heating?
Slightly higher airflow improves capacity and keeps head pressure sensible.
About this calculator
- Built and reviewed by James Whitfield · How we build and test calculators
- Report an error
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.