Heat pump vs furnace: how to decide without a sales script

A heat pump moves heat. In summer it dumps house heat outside (that’s air conditioning). In winter it pulls heat from outdoor air and dumps it inside. A gas furnace only makes heat, so you still need a separate AC if you want cooling.

If your AC is dying and the furnace is old, you are shopping for one machine that replaces two. If the furnace is new and only the AC failed, replacing just the AC is often the rational move.

We do not sell equipment. We have not run a load calculation on your house.

What the job actually costs

EnergySage’s 2026 heat-pump buying guide puts average installation at $15,393, with brand-level marketplace averages much wider — Carrier around $12,500, Trane around $19,000, Daikin around $23,000, Mitsubishi around $31,000 in their quoted set. Ductless Mitsubishi systems show high HSPF2 / SEER2; Quilt-style room units are priced per room, not as a whole-house swap.

EnergySage: Best heat pumps

Those are marketplace quotes, not a bid for your address. Cold-climate equipment, new ductwork, electrical-panel work, and “while you’re here” line-set runs move the number more than the logo on the condenser.

A central AC-only replacement is cheaper on day one because it does not heat. Treat that as an incomplete comparison unless you already have a working furnace you intend to keep.

The federal credit you should not bake into a 2026 bid

The IRS Energy Efficient Home Improvement Credit (25C) is for qualifying property placed in service on or after January 1, 2023, and before December 31, 2025. Qualifying heat pumps sat in the $2,000 per year bucket (30% of eligible cost, capped).

IRS: Energy Efficient Home Improvement Credit

If the unit is placed in service in 2026, do not subtract $2,000 from the quote because a salesperson still has 2025 leave-behind. State and utility rebates may still exist; those are local. Confirm “placed in service” vs “ordered.”

When a heat pump is the default

• You need heat and cooling in the next few years, and you are in a climate where modern cold-climate units are specified (ask for the minimum operating temperature and capacity at that temperature, not just SEER2).
• Your current heat is electric resistance. A heat pump uses less electricity to deliver the same heat; that is physics, not a rebate flyer.
• The furnace is also near end of life, so you are not throwing away a five-year-old gas appliance.

When a furnace + AC (or dual fuel) is still reasonable

• Extreme cold, cheap gas, expensive electricity, and a furnace that still has years left.
• The Washington Post’s 2025 modeling of one house showed a cheap heat pump with a long payback if you were replacing a working system — and in a Chicago-rate scenario, a minimum-efficiency heat pump could raise bills. Operating cost is outdoor temperature × your rates × the unit’s real winter capacity.

Washington Post (archived): home energy upgrade math

Dual fuel (heat pump down to a cutoff, gas below that) is the adult version of this argument. It costs more hardware. It can be the right spec.

Do the shell first if the house leaks

A tight, insulated house needs a smaller machine. Buy insulation and air sealing before you let someone size a 5-ton unit for a 3-ton problem. If a quote has no Manual J (or equivalent load calc) and no mention of ducts or envelope, it is a catalog, not an engineering job.

What a serious quote includes

1. Heating and cooling load (Manual J or named equivalent), not a square-foot rule of thumb.
2. Duct assessment (Manual D / leakage), or a ductless plan with head count and line-set routes.
3. Electrical: breaker space, wire size, whether a panel upgrade is in or out of scope.
4. Capacity at your design temperature, not only nameplate SEER2 / HSPF2.
5. Warranty in writing: parts, compressor, labor, and whether it requires a factory-trained installer.
6. What is excluded: permits, condensate, pad, line-hide, thermostat, old-equipment haul-away.
7. Rebate paperwork: who files it.

Get two or three quotes. If one is 40% cheaper, find the missing line item before you celebrate.

What the marketplace averages actually are

EnergySage’s 2026 cost pages split the $15,393 average into system types: ducted about $14,529, hybrid (heat pump plus furnace) about $14,353, ductless whole-home about $25,957 before incentives. After state and local incentives in their tables, hybrids drop more than ducted because programs often still like dual fuel. Federal 25C is not in those 2026 “after incentives” columns for new installs.

EnergySage: heat pump cost

Ductless looks “expensive” until you remember it is priced per indoor head. EnergySage has described extra zones as adding up to around $8,000 per zone depending on labor and line sets. A four-head house is not comparable to a one-condenser ducted changeout. If you have no ducts, adding a full duct system ($2,000 to $10,000+ in their retrofit range) can erase the ducted “savings.”

Brand-level install averages on their “best heat pumps” table are a different cut of the same marketplace: Carrier around $12,500, Trane around $19,000, Daikin around $22,700, Mitsubishi around $30,900. Those are not MSRPs. They mix ducted and ductless, mild and cold climates, easy attics and three-story townhouses. Use them to sanity-check a bid, not to pick a winner by logo.

EnergySage also quotes a median bill savings of $300–$650 a year when people switch from traditional heat. That is a median over mixed fuels and mixed rates. Oil and propane houses save more; cheap-gas / expensive-electric houses can save little or lose. The Washington Post model is the cautionary tale: payback is not a moral fact.

Dual fuel without the slogan

Hybrid in the EnergySage table is a heat pump that hands off to a gas furnace below a lockout temperature. You keep the gas meter. You get AC and mild-weather heat from the pump. You stop asking a 2-ton head to hold 5°F without backup.

It is the right spec when:

• Winter design temperature is brutal and your electric rate is high relative to gas.
• You already have a decent furnace and dying AC.
• The bid includes a real lockout setpoint and a control that actually switches, not a furnace that never shuts up.

It is the wrong spec when someone uses “hybrid” to sell you a cheap heat pump that cannot heat, plus a new furnace you did not need.

Electrical and the 100-amp panel

Heat pumps are large 240-volt loads. A 100-amp service that already feeds electric range, dryer, and water heater may not take a heat pump without load management or a service upgrade. Put that question on the first call, not at install week. The Level 2 charger article in this desk is the same electrical story with a different appliance.

How to decide in one afternoon

1. What is dying? AC only, furnace only, both, or nothing (you are shopping on purpose).
2. What is the fuel you have, and what did you pay per therm and per kWh last January?
3. Is the attic a disaster? If yes, read weatherize before the heat pump before you sign.
4. Get two bids that use the quote checklist — load, ducts, design-temperature capacity, electrical, exclusions.

If both bids refuse to write a load, you do not have bids yet.

Next

The quote checklist and the weatherization guide are live. Use them in that order: house, then bid, then machine.