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Ducted vs ductless heat pumpsDucted heat pumps deliver air through a duct system from one indoor coil, while ductless (mini-split) systems put one or more indoor units directly in the rooms they serve.
Heat pump ratings explained: SEER2, EER2, HSPF2 and AHRI certificatesSEER2, EER2 and HSPF2 are the federal efficiency ratings used since January 1, 2023, and an AHRI certificate shows them for one exact matched system.
Heat pump refrigerants: R-410A, R-32 and R-454BAs of October 2026, new residential heat pumps in the U.S. must use a refrigerant with a global warming potential under 700, such as R-32 or R-454B, while existing R-410A systems can still be serviced.
Heat pumps in cold weatherAn air-source heat pump's capacity and efficiency both fall as the outdoor temperature drops; cold-climate models are tested at 5°F and must keep a COP of at least 1.75 there.
How heat pumps workA heat pump uses electricity to move heat between indoors and outdoors with a refrigerant loop, and a reversing valve lets the same equipment heat in winter and cool in summer.

Dual fuel and hybrid heat pump systemsA dual fuel system pairs an electric heat pump with a gas or propane furnace and switches between them at an outdoor temperature you can choose based on capacity and fuel prices.
Heat pump buying checklistWhat to ask a contractor for before you sign, including the AHRI certificate, Manual J and S, line set plan, electrical scope, permits and warranty registration.
How to read a heat pump quoteA useful quote names every component by model number, ties the efficiency ratings to an AHRI certificate, and states what is included and excluded so two quotes can be compared line by line.
Variable-speed vs single-stage heat pumpsSingle-stage heat pumps run at one capacity, two-stage at two, and variable-speed (inverter) units adjust continuously, which changes cycling, humidity control and cold-weather output.

Manual J, Manual S and Manual D explainedACCA Manual J calculates a home's heating and cooling loads, Manual S picks equipment to match them, and Manual D designs the ducts; rules of thumb based on square footage tend to oversize.
Thermal and economic balance pointsThe thermal balance point is the outdoor temperature below which a heat pump alone cannot heat the house; the economic balance point is the temperature below which another heat source is cheaper to run.

Heat pump electrical requirementsThe wire and breaker for a heat pump are sized from the nameplate MCA and MOCP, and whether the panel can take the load is decided by an NEC load calculation, not the panel's size alone.
Permits and inspections for heat pumpsMost heat pump installations need a mechanical permit and often an electrical permit, and the inspection checks code items such as sizing, electrical, condensate and line set; rules vary by jurisdiction.
What a good heat pump installation looks likeA good installation follows the manufacturer's manual for line set limits, nitrogen brazing, pressure testing, evacuation, charge, condensate, clearances and snow elevation, and records the measurements.

Heat pump backup heat and lockout temperaturesAux heat supplements the heat pump automatically, emergency heat replaces it by hand, and outdoor lockout settings decide at what temperatures each one is allowed to run.
Heat pump defrost cyclesIn cold, damp weather a heat pump periodically reverses for several minutes to melt frost off the outdoor coil, and steam, a whoosh and a stopped outdoor fan are normal parts of that.
Heat pump filters and maintenanceCheck filters monthly and change or clean them at least every three months (ductless filters more often), keep the outdoor unit clear, and have a technician service the system once a year.
Heat pump noiseOutdoor heat pump sound is rated in A-weighted decibels under AHRI Standard 270, variable-speed units are quieter at low speed and louder at full speed, and placement affects what you hear.
Heat pump thermostat settings and setbacksWith a heat pump, keep setbacks small or use a thermostat with heat pump recovery logic, because a deep setback can make the system recover on backup heat.

Heat pump not heatingCheck the thermostat mode and setpoint, breakers and disconnects, the filter, vents and the outdoor unit first; anything involving refrigerant, electrical components or repeated faults needs a technician.
Heat pump short cyclingShort cycling means the heat pump turns on and off in short bursts, commonly because it is oversized for the load, and also because of thermostat placement, airflow or refrigerant problems.
Ice on the outdoor unitA light frost that clears during defrost is normal; heavy ice that covers the coil, blocks airflow or does not clear within hours needs attention, and you should never chip ice or pour hot water on the unit.

Federal tax credit for heat pumps (25C)The federal 25C credit paid 30% of a qualifying heat pump's cost up to $2,000 a year, and it ended for equipment placed in service after December 31, 2025.
Heat pump rebates and incentivesHeat pump incentives come from utilities, states and federally funded state programs, each with its own equipment rules, contractor rules and limits on combining.