Compare heat pumps and air conditioners across efficiency ratings, climate zones, upfront cost, operating cost, and federal tax credits to make the right choice.
A standard central air conditioner does exactly one thing: it moves heat from inside your home to the outdoors. It cools. When winter comes, you need a separate heating system — a furnace, boiler, or electric resistance heat.
A heat pump is an air conditioner that can also run in reverse. In summer it works just like an AC. In winter it extracts heat from outdoor air (even cold air contains usable heat energy) and moves it inside. One system handles both seasons.
An air conditioner runs the refrigeration cycle in one direction only:
A heat pump adds one key component: the reversing valve (also called a four-way valve). In cooling mode it operates identically to an AC. In heating mode the reversing valve switches refrigerant flow direction — the outdoor coil becomes the evaporator (absorbing heat from outside air) and the indoor coil becomes the condenser (releasing heat indoors).
| Rating | What It Measures | Units | Where Used |
|---|---|---|---|
| SEER2 | Seasonal cooling efficiency (2023+ test standard) | BTU/Wh | Air conditioners and heat pumps (cooling) |
| HSPF2 | Seasonal heating efficiency (2023+ test standard) | BTU/Wh | Heat pumps (heating) |
| COP | Coefficient of performance — heating output / electrical input | Ratio (unitless) | Heat pumps; COP 3 = 300% efficiency |
As outdoor temperature drops, a heat pump's heating capacity decreases while your home's heat loss increases. The temperature where the heat pump output exactly meets the building's heat demand is called the balance point — typically 30–40°F for a standard heat pump. Below the balance point, supplemental heat is required via electric resistance auxiliary heat strips.
The Northeast Energy Efficiency Partnerships (NEEP) cold-climate heat pump (ccHP) specification requires rated heating capacity down to -13°F (-25°C). These units use inverter-driven variable-speed compressors and flash injection technology to maintain capacity at low temperatures. Balance points as low as -4°F to -13°F — no backup heat needed in most North American climates.
| Climate Zone | Examples | Best Choice |
|---|---|---|
| Hot-Humid (Zone 1-2) | Miami, Houston, Phoenix | Heat pump |
| Mixed (Zone 3-4) | Atlanta, Charlotte, DC | Heat pump |
| Cool (Zone 5) | Chicago, Denver, Columbus | Cold-climate heat pump or hybrid |
| Cold (Zone 6-7) | Minneapolis, Buffalo, Vermont | Hybrid or gas + AC |
| Very Cold (Zone 8) | Fairbanks, northern Canada | Gas furnace + AC |
The Inflation Reduction Act (IRA) Section 25C provides a 30% federal tax credit on heat pump installation, up to $2,000 per year through 2032. Must meet ENERGY STAR cold-climate requirements (HSPF2 ≥ 8.1 for split systems). State and utility rebates may stack on top.
Topics covered
NATE Certification - Extended Practice Exam
✨ Premium ContentGo beyond the free practice questions with a full-length paid exam bank.
Residential HVAC Design — Start to Finish (Full Access)
✨ Premium ContentA structured, paid professional training program for this discipline.
Single-Family Residence HVAC Design Drawing Set (Full Access)
✨ Premium ContentA zoomable interactive reader — free preview, then unlock the full set.
Chiller Sizing Calculator
✨ Premium ContentA paid interactive calculator or 3D simulator for this discipline — part of the All-Access Pass.
📬 Get new engineering guides in your inbox
New calculators, interactive readers, and reference guides — no spam, unsubscribe anytime.
Put this knowledge to work on your iPhone
Browse our full catalog of professional iOS apps — from electrical code tools to AI builders.
Browse All 95+ Apps