WHOLE-HOUSE HEAT PUMP SIZING

Heat pump size calculator

Trying to work out how big a heat pump your home needs? Put in the basics below and we will give you a rough capacity range. It is a way to prepare for a quote, not a substitute for a proper load calculation.

HOME DETAILS

Start with the house

Give us the details you are likely to know. The final answer still depends on the rooms, the ductwork, the weather where you live, and how leaky the building is.

ROUGH CAPACITY RANGE
38,700–52,300 BTU/h

The larger estimate here is the heating load. That is the load the system has to cover first.

Estimated cooling33,000 BTU/h
Estimated heating45,500 BTU/h
Nearest common equipment size48,000 BTU/hCheck the manufacturer's capacity at your local design temperature

Do not order from this number alone. Ask for a room-by-room Manual J calculation before choosing the equipment.

BEFORE YOU CHOOSE A UNIT

The installer still has to size the system

Heating and cooling are different

A heat pump has to keep up in winter and summer. The colder it gets, the more its available heating capacity and backup-heat plan matter.

The house changes the answer

Ceiling height, insulation, windows, sun, climate, and occupancy all move the estimate. None of them can replace room-by-room measurements.

Questions worth asking

Ask to see the Manual J result, the capacity at your design temperature, the backup-heat strategy, the duct assessment, and the commissioning plan.