Quick answer
A furnace makes heat by burning natural gas; a heat pump moves heat from the outdoor air into your home — and reverses in summer to cool it. Because moving heat takes far less energy than making it, a heat pump wins on efficiency in our climate. The furnace wins on upfront price and hotter air at the register. Which one wins for you comes down to your fuel situation, whether you want cooling, and how long you plan to stay.
- A furnace only heats. A heat pump heats and cools — one system replaces two.
- Seattle-area winters rarely drop below freezing, which is exactly where heat pumps do their best work.
- A furnace wins on upfront cost and hot, fast air. A heat pump wins on efficiency, rebates, and year-round comfort.
- Washington HEAR and PSE rebates apply to heat pumps. There are no equivalent rebates for a new gas furnace.
Last updated: 2026-07-16 · Written & reviewed by the Eco field team
Furnace vs heat pump at a glance
| Gas Furnace | Heat Pump | |
|---|---|---|
| What it does | Heats only | Heats and cools |
| Installed cost | ≈ $6K–$12K (like-for-like swap) | ≈ $17K–$30K+ ducted, before rebates |
| Efficiency | 80–96%+ AFUE — under 1 unit of heat per unit of fuel | 2–4 units of heat per unit of electricity |
| Air at the register | Hot — 120–140°F, short blasts | Warm — 90–100°F, longer, steadier cycles |
| Cooling | None — needs a separate AC | Built in |
| Fuel | Natural gas (plus electricity for the blower) | Electricity only |
| Rebates (2026) | None | WA HEAR (income-qualified) + PSE |
| Typical lifespan | 8–10 years (PNW typical) | 15–20 years with annual service |
| Best fit | Gas service, good ducts, tight budget | Most Puget Sound homes — especially furnace + AC replacements |
Cost ranges are the typical installed pricing we publish for single-family Puget Sound homes — your home's specifics set the real number.
When is a furnace still the right call?
When you have gas service, good ducts, and a working AC (or genuinely don't want cooling) — a like-for-like swap is the cheapest path to reliable heat. When upfront budget is the deciding constraint and rebate eligibility doesn't change the math for you. When your time horizon is short — you're moving within a few years and won't be there to collect the efficiency savings. And when your furnace died in January and you need heat this week: a swap is usually a one-day job.
When does a heat pump win?
When your furnace and AC are both aging — one heat pump replaces both, and the combined-project math usually favors it. When you heat with electric resistance today — this is the single biggest bill-cutting move available to you. When you want cooling and don't have it — you're buying an AC that happens to heat at 2–4× efficiency. When you qualify for HEAR income-based rebates, the upfront gap can shrink dramatically. And when you're staying put and playing the long game on bills, comfort, and carbon.
How does each one work, in plain English?
A gas furnace is a controlled fire in a metal box. Gas burns inside a heat exchanger, a blower pushes your home's air across the hot metal, and the warmed air heads out through the ducts. Simple, proven, and unbothered by whatever the weather is doing outside. A heat pump doesn't make heat — it moves it. Even a 45° January morning holds plenty of heat energy, and the refrigerant in the outdoor coil runs colder than the outside air, so heat flows into it. A compressor concentrates that warmth and releases it inside. In summer a reversing valve flips the loop and moves your home's heat outdoors.
Why does Puget Sound weather tilt this decision?
Heat pump efficiency depends on outdoor temperature — the colder it gets, the harder the system works. That's a real concern in Minnesota. It's barely one here. Seattle's winter design temperature sits in the 20s, most winter days hover in the 40s, and modern cold-climate heat pumps hold strong output well below anything our region typically sees. Meanwhile, our summers have changed: air conditioning went from a luxury to an expectation in much of Puget Sound over the last decade, and a heat pump answers that in the same box. If you're weighing a furnace replacement and an AC install as two separate projects, a heat pump is quietly bidding on both jobs at once.
What about operating cost?
It depends on what you're switching from. Replacing electric resistance heat — wall heaters, baseboards, an electric furnace — a heat pump typically cuts heating energy use by half or more, because resistance heat makes one unit of heat per unit of electricity and a heat pump moves 2–4. Against natural gas, the math is closer and moves with fuel prices: gas is a cheap fuel burned in a less efficient machine; electricity is a pricier fuel used by a far more efficient one. For most local homes the running costs land in the same neighborhood, with the heat pump pulling ahead as rates and equipment efficiency shift.
Can't pick a side? Dual-fuel runs both
A dual-fuel (hybrid) system pairs a heat pump with a gas furnace and switches between them automatically — the heat pump carries the load most of the year, and the furnace takes over on the rare mornings cold enough to favor it. You keep gas as a built-in backup and still bank heat pump efficiency for 90% of the season. The honest tradeoffs: it's the most expensive option upfront, there are two systems to maintain, and the switchover settings have to be dialed in correctly — set wrong, they quietly erase the savings you paid for.
Washington rebates in 2026: what's actually still available?
The federal 25C tax credit — the one worth up to $2,000 on heat pumps — ended December 31, 2025. Any page still promising it for a 2026 installation is out of date. What's live in Washington right now: WA HEAR rebates (Dept. of Commerce) — income-qualified households can receive up to $8,000 toward a heat pump, applied at point of sale through a participating contractor, funds first-come, first-served. PSE rebates — Puget Sound Energy offers heat pump rebates, with larger income-qualified tiers. And nothing for gas furnaces: current programs are built to move homes toward heat pumps, and no equivalent rebate exists for new gas equipment. Eligibility rules shift and funds run out — we confirm what you qualify for and handle the paperwork as part of every heat pump estimate.
Pros and cons, honestly
Gas furnace
Pros
- Lower upfront cost — ≈$6K–$12K for a like-for-like swap (client-published range)
- Hot, fast air at the register — 120–140°F blasts
- Unbothered by outdoor temperature; a swap is usually a one-day job
Cons
- Heats only — a separate AC is still needed for cooling
- No Washington rebates apply (2026)
- 8–10 year PNW-typical lifespan
Heat pump
Pros
- 2–4 units of heat per unit of electricity — and it cools in summer
- WA HEAR (income-qualified) + PSE rebates apply
- 15–20 year lifespan with annual service
Cons
- Higher upfront cost — ≈$17K–$30K+ ducted before rebates (client-published range)
- Warm 90–100°F air in longer, steadier cycles — a feel some furnace households need a season to adjust to
“Heat pumps blow cold air” — the honest version
Here's what's actually going on. A furnace delivers short blasts of 120–140°F air; a heat pump delivers longer, steadier cycles of 90–100°F air. That's warmer than your skin — it is heating your home — but it doesn't feel like the hair-dryer rush furnace owners are used to. Some people prefer the even, quiet warmth immediately. Some lifelong furnace households need a season to adjust. Nobody's imagining the difference, and pretending it doesn't exist is how homeowners end up unhappy with a perfectly good install.
The verdict, by situation
Heat pump
The default answer for most Puget Sound homes
Mild marine winters are its efficiency sweet spot, it replaces the AC you increasingly want in August, and it's the only option Washington rebate programs fund in 2026.
Gas furnace
Still right for the quick, budget-driven swap
Gas service, sound ducts, a working AC, and a tight budget or short ownership horizon — a like-for-like swap is the cheapest path to reliable heat, often done in a day.
Dual-fuel
The can't-pick-a-side answer
The heat pump carries ~90% of the season; the furnace takes the rare coldest mornings automatically. Most expensive upfront, two systems to maintain — but gas backup stays.
Which Washington homes this fits
Post-war ducted gas home (Seattle, Everett ramblers)
The classic candidate: existing ducts carry a ducted heat pump directly, and if the furnace and AC are both aging, one system replaces two.
Electric-resistance home (baseboards, wall heaters)
Skip the furnace conversation — a heat pump is the single biggest bill-cutting move available, typically halving heating energy or better.
Newer furnace, no cooling yet
Consider dual-fuel: keep the healthy furnace as backup, add the heat pump for efficient heat plus the summer cooling the house never had.
Short-horizon or budget-first household
If you're moving within a few years and rebates don't change your math, the like-for-like furnace swap remains the honest budget answer.
How we build this guidance
- We install and service both — furnaces and heat pumps, every week, across Seattle and Everett homes. No stake in which one you pick.
- Numbers come from real local installs and permits, not national averages.
- We tell you the tradeoffs the brochure won't — including the ones that cost us easy sales.
Methodology: Cost ranges reflect typical installed pricing for single-family Puget Sound homes; efficiency figures use AFUE ratings and field-realistic heat pump COP ranges rather than lab-best numbers; rebate details verified against program sources as of July 2026.
Ready for the next step?
Get a free estimate for your actual house, not a hypothetical one — honest numbers and rebate eligibility checked before any work begins.
Continue exploring
- Learn: How do heat pumps work? →
- Learn: What does a heat pump cost to run in Seattle? →
- Learn: Washington HVAC rebates explained →
- Evaluate: Heat pump vs gas furnace — the decision framework →
- Compare: Heat pump vs air conditioner — what's the difference? →
- Compare: Furnace repair vs replacement — how to make the call →
- Compare: Single-stage vs two-stage vs variable-speed furnaces →
- Book: Heat pump service and estimates →
Common questions
Will a heat pump keep my house warm in a Seattle winter?
Yes. Seattle's coldest typical mornings sit in the 20s, and modern cold-climate heat pumps hold strong output well below that. Our winters are mild by heat pump standards — this is one of the best heat pump climates in the country.
Is a furnace or a heat pump cheaper to run here?
Versus electric resistance heat, the heat pump wins decisively — usually half the heating energy or better. Versus natural gas, they're in the same neighborhood for most local homes, and the answer shifts with PSE gas and electric rates. The heat pump also replaces your AC's summer usage with the same efficient equipment.
Do I have to remove my furnace to add a heat pump?
No. A dual-fuel setup keeps a gas furnace as backup and lets the heat pump handle most of the year. If your furnace is newer and compatible, it can often stay.
Which one lasts longer?
In the Puget Sound, the heat pump: furnaces here typically run 8–10 years, while air-source heat pumps last 15–20 with annual service. Maintenance moves both numbers more than the brand name does — full details in How Long Does an HVAC System Last in the PNW?
Does a heat pump really replace my air conditioner?
Yes — a heat pump is an air conditioner that can also run in reverse. In cooling mode it works exactly like a standard AC of the same efficiency class. One outdoor unit, both seasons.
Sources & references
Equipment ratings, program details, and industry figures on this page come from manufacturers and primary sources, linked below. Verify program status and requirements for your home where applicable.
Heat pump performance
- How air-source heat pumps move heat, and their efficiency advantage over electric resistance heating (roughly 50% less electricity) — US DOE Energy Saver — Heat Pump Systems
Washington rebates
- HEAR: income-qualified heat pump rebates up to $8,000, applied at point of sale (funds first-come, first-served) — WA Dept. of Commerce — Home Electrification and Appliance Rebates (HEAR)
- Puget Sound Energy residential heat pump rebates — Puget Sound Energy — residential rebates
Equipment lifespan (our published data)
- Puget Sound service-life figures: furnaces 8–10 years, central ACs 12–15, heat pumps 15–20+ with annual service — Eco — How Long Does an HVAC System Last in the PNW?