Locally-owned since 1977 • Licensed, bonded and insured in Washington (WA Contractor Reg. #HOMECCA785BD) • NATE-certified technicians • Carrier Factory Authorized Dealer
Furnace Replacement in Federal Way, WA
When a furnace is worn out, unsafe or too costly to keep repairing, we replace it with a new gas furnace, an electric furnace or a heat pump system sized to your home. Federal Way replacements are handled by our Sumner branch: call (425) 645-0404 or send the form, and a comfort advisor will visit, measure the home and give you written options with incentives and financing. The estimate is free.
Federal Way homes get both natural gas and electricity from Puget Sound Energy (City of Federal Way, Who Do I Contact), so all three options are open to most homeowners here.
What a new furnace costs
| Item | Seattle-area estimate |
|---|---|
| Average installed furnace | About $4,683 |
| Common range | $2,762 to $6,683 |
| Natural gas furnace | $3,800 to $10,000 |
| Electric furnace | $2,000 to $7,000 |
| Labor share of the job | About 20 to 30 percent |
Source: Angi, Seattle new furnace costs, updated July 2026. These are published estimates, not our prices. Venting changes, duct repairs, a new thermostat or electrical work can move the price, and your written estimate lists each item.
Get a free estimateAn in-home visit and a written, upfront price before any work begins.
Signs it is time to replace
- The furnace is 15 to 20 years old or more.
- A technician found a cracked heat exchanger or a failed safety test.
- Repairs are getting frequent, or one repair would cost a large share of a new unit.
- Some rooms never warm up, or the furnace runs constantly on cold days.
- Your gas bills keep rising even though your habits have not changed.
- You hear banging, rumbling or squealing when it starts.
If the furnace is younger and the problem is a single part, our Federal Way heating repair team can usually fix it instead.
Your replacement options
| Option | Why choose it |
|---|---|
| High-efficiency gas furnace | Lowest change from what you have; strong heat on the coldest days |
| Gas furnace plus heat pump (dual fuel) | Heat pump runs most of the year, furnace covers the cold; adds cooling; PSE rebate |
| Ducted heat pump with electric backup | No gas bill for heat; cooling included; best when leaving gas |
| Electric furnace | Simple and low cost to install where there is no gas, but costly to run |
We price at least two of these side by side. For many Federal Way homes with PSE gas, dual fuel is worth a look because PSE pays $1,500 toward the heat pump, with up to $2,400 more for income-qualified households (PSE hybrid heat pump rebate). See our heat pumps in Federal Way page for more.
Venting and your water heater
High-efficiency gas furnaces vent through plastic pipe out a side wall or the roof and drain condensate, so the old metal flue is no longer used by the furnace. If a gas water heater shares that flue, it may be left venting alone through a chimney sized for two appliances. We check this on gas furnace replacements and line or resize the vent when needed, so the water heater keeps venting safely.
Ducts, filters and airflow
A new furnace only performs as well as the ducts behind it. Older Federal Way homes often have crawlspace ducts that have come apart, missing insulation and return air paths too small for the blower. We inspect the ducts during the estimate and tell you what needs sealing or resizing. A new filter cabinet with a deeper media filter is an easy upgrade at the same time.
Homes built before 1990
Many Federal Way homes are older ramblers and split-levels, built well before the newer townhomes around the city center. In homes from the 1960s and 1970s, the old furnace and ducts may be wrapped in materials that contain asbestos. If we see suspect material, we stop and recommend testing before any of it is disturbed. We also check gas piping, the electrical supply to the furnace and clearances around it.
Replacing a furnace in a rental
Plenty of Federal Way homes are rentals, so many furnaces here heat someone else’s home. If you own a rental, we can plan the estimate visit and the installation around the tenant’s schedule. The written estimate goes to you, and the tenant gets a start time and a heads-up that the heat will be off for most of the day.
If the furnace fails in midwinter
A furnace rarely fails at a convenient time. If yours stops on a cold night, space heaters on separate circuits can bridge the gap, but keep them clear of bedding and curtains. When a repair can keep the old furnace running safely for a few weeks, we will tell you, so you can compare replacement options without rushing. If it is unsafe to run, we shut it off and explain why.
Thermostats and controls
A new furnace is a good time to replace an old thermostat. Variable-speed and two-stage furnaces run best with a thermostat that can control their stages, and dual fuel systems need one that knows when to switch from the heat pump to the furnace. We set it up and show you how the schedule works.
Permits and inspection
The City of Federal Way issues mechanical permits, and residential applications are filed online through MyBuildingPermit (City of Federal Way, Permit Center). A furnace replacement needs one, and new gas piping or electrical work may need more. We pull the permits and schedule the city inspection after installation.
What installation day looks like
Most replacements take a single day. The crew protects floors, shuts off gas and power, removes the old furnace, sets the new one, connects gas, venting, wiring and ducts, and installs the thermostat. Then they start it up, test combustion and safety controls, check airflow and temperature rise, and walk you through the filter and settings.
Before and after: what to expect on your bill
Moving from a 20-year-old furnace to a new high-efficiency one burns noticeably less gas for the same heat. Adding a heat pump shifts most of the heating to electricity, which in our mild climate is usually cheaper to run than resistance heat. Your comfort advisor can walk you through the tradeoffs for your home.
Why Home Comfort Alliance
We have served Puget Sound homeowners since 1977 and are licensed, bonded and insured in Washington (WA Contractor Reg. #HOMECCA785BD). We are a PSE Trade Ally for HVAC and handle rebate paperwork. Learn more about our furnace replacement services or see all Federal Way services.
Warranty and Home Comfort Club
We support the manufacturer’s warranty on covered equipment parts, and we stand behind our furnace installations with a 1-year labor warranty from installation.
Join our Home Comfort Club, a monthly membership starting at $15 a month, and a new system we install gets extended labor coverage for as long as your membership stays active, up to 5 years from installation. Ask your technician or comfort advisor for the current plan details.
Federal Way furnace replacement FAQ
How much does a new furnace cost in Federal Way?
Seattle-area data puts the average installed furnace at about $4,683, with most jobs between $2,762 and $6,683; gas furnaces run $3,800 to $10,000 and electric furnaces $2,000 to $7,000 (Angi, Seattle new furnace costs, updated July 2026). Your free written estimate reflects your home.
How long does furnace replacement take?
Most straight replacements take one day. Converting to a high-efficiency furnace with new venting, or adding a heat pump, can take a second day.
Is there a rebate for a new furnace in Federal Way?
PSE supplies gas and electricity in Federal Way (City of Federal Way, Who Do I Contact). As of September 2026, PSE pays $1,500 toward a heat pump added to a gas furnace, plus up to $2,400 through Efficiency Boost (PSE hybrid heat pump rebate). Ask us to price a dual fuel option alongside a furnace alone.
Do I need a permit to replace a furnace in Federal Way?
Yes. Furnace replacement needs a mechanical permit from the City of Federal Way, filed online through MyBuildingPermit (City of Federal Way, Permit Center). We pull it and schedule the inspection.
What size furnace do I need?
Not necessarily the size you have now. Many older furnaces were oversized. Our comfort advisor measures the home and sizes the new one to its actual heat loss.
Are furnace replacement estimates free?
Yes. Estimates for replacements and new installations are free.
What warranty comes with your work?
We support the manufacturer’s warranty on covered equipment parts, and our labor warranty covers installations for 1 year from installation. Home Comfort Club members (monthly membership starting at $15 a month) with a new system installed by Home Comfort Alliance get extended labor coverage for as long as their membership stays active, up to 5 years from installation.
Why Choose Home Comfort Alliance in Federal Way?
Your Comfort is Our Promise
We promise...
Reliable heating, air conditioning, plumbing and electrical service, all from one trusted company.
To educate and guide you through your options so you’ll find the right solution at the right price.
Knowledgeable and respectful workers who ensure both your own comfort during the installation process, and lasting comfort from your home systems.
Outstanding service, communication, and follow-up, so your home is comfortable now and for years to come.
Get a furnace replacement estimate in Federal Way
A Sumner-based comfort advisor will measure your home and give you written options with incentives and financing.
Get an estimate
A Sumner-based comfort advisor will call you to set up your visit.