What determines heat-pump operating cost, including outdoor temperature, heating load, equipment efficiency, supplemental heat and electricity rates.
Heat-pump operating cost varies substantially through the season because both the home's heating load and the equipment's operating conditions change with outdoor temperature.
As weather becomes colder, the home typically needs more heat. Heat-pump capacity and efficiency also change with outdoor conditions, and some systems use supplemental heat when required.
A useful cost analysis therefore needs more than the equipment's nominal size or HSPF2 rating.
Heating demand rises as the indoor-outdoor temperature difference increases.
Capacity and efficiency vary with operating conditions.
Electric resistance or dual-fuel backup can materially change operating cost.
Utility pricing converts energy consumption into actual dollars.
Insulation, air leakage, windows and home size determine how much heat is required.
Balance points, staging and thermostat strategy affect when supplemental heat operates.
Equipment efficiency describes how effectively equipment performs under defined conditions. Your utility consumption also depends on weather, thermostat settings, building heat gain or loss, ductwork, system sizing, maintenance and how many hours the equipment operates.
Before replacing functioning equipment solely for a higher efficiency rating, evaluate low-cost problems such as thermostat schedules, dirty filters, blocked airflow, duct leakage and building-envelope deficiencies. Major equipment replacement should be evaluated on installed cost, expected savings, comfort and remaining equipment life.
Evaluate efficiency as an investment, not just a rating.
Keep equipment and airflow operating as intended.
Understand how air distribution affects performance.
Use Central HVAC's planning and evaluation tools.
Use the Buying Guides and Homeowner Tools to evaluate equipment efficiency, system age, replacement budget and contractor proposals together.
Understand the ratings behind energy-performance claims.
Apply efficiency information to replacement decisions.