Locally-owned since 1977 • Licensed, bonded and insured in Washington (WA Contractor Reg. #HOMECCA785BD) • WA Electrical Contractor Lic. #HOMECCA782DC • NATE-certified technicians • Carrier Factory Authorized Dealer • Mitsubishi Electric Diamond Dealer • Lennox Premier Dealer
Heat pump installation on Mercer Island, WA
Home Comfort Alliance installs and replaces ducted, ductless and hybrid heat pumps across Mercer Island from our Redmond branch, with a room-by-room Manual J load calculation and the required permits on every installation.
Energy Smart Eastside network installer and approved PSE contractor (Trade Ally)
Mercer Island homes can combine Energy Smart Eastside's $1,000 point-of-sale rebate with a PSE rebate based on how they heat today. The City of Mercer Island issues both the mechanical and electrical permits, we pull them, and most installations take 4 to 10 hours.
Call (425) 645-0404 or book online. Need a repair instead? See heat pump repair.
More heating services in Mercer Island
Is a heat pump right for your Mercer Island home?
Usually, yes. A heat pump heats and cools with one system, and what you heat with today decides the best setup and which rebates stack.
| What you heat with today | Usual heat pump option | Rebates to check |
|---|---|---|
| PSE gas furnace | Hybrid: a heat pump added to your furnace, or a full switch | ESE $1,000; PSE $1,500 hybrid, or $4,000 if income-qualified and switching off gas |
| Oil furnace | Ducted heat pump on the existing ducts | ESE; PSE does not cover oil heat |
| Electric furnace, baseboards or wall heaters | Ducted or ductless heat pump | ESE $1,000; PSE $1,500 |
| Older heat pump, out of warranty | Ducted cold-climate replacement | PSE $1,500 upgrade; ESE rules apply |
Energy Smart Eastside and PSE rebates on Mercer Island (updated November 2026)
Mercer Island is part of Energy Smart Eastside, and PSE supplies the island's electricity and natural gas, so most homes can combine an ESE rebate with a PSE rebate based on how they heat today.
| Program | Amount | Who qualifies |
|---|---|---|
| Energy Smart Eastside | $1,000 at the point of sale | Qualifying heat pump installed by a network installer |
| Energy Smart Eastside bonus | Up to $5,000 more | Income-qualified households (below 150% of King County median income) installing a fully electric system |
| PSE (electric) | $1,500, plus up to $2,400 Efficiency Boost | Replacing baseboards, wall heaters or an electric furnace |
| PSE (electric) | $1,500 heat pump upgrade | Out-of-warranty, centrally ducted all-electric heat pump; cold-climate replacement |
| PSE (natural gas) | $1,500 hybrid | PSE gas furnace homes adding a ducted heat pump (30°F switchover or lower) |
| PSE (natural gas) | $4,000 | Income-qualified PSE gas customers switching to a heat pump; apply within 30 days of install |
| PSE instant discount | $300, $400 or $600 | Qualifying new heat pumps, by efficiency tier |
Energy Smart Eastside rebates are only available through installers on its network list, and Home Comfort Alliance is on that list. The hybrid route gets ESE's $1,000 but not the income bonus. Some PSE offers can't be combined, so we check which option pays you the most and handle the paperwork. The federal 25C tax credit ended for equipment installed after December 31, 2025 (Energy Smart Eastside rebates, our Energy Smart Eastside guide, PSE rebates).
Switching from oil heat
PSE's conversion rebate does not cover oil heat, and Seattle's Clean Heat rebate is for Seattle homes only. Energy Smart Eastside covers replacing an existing furnace, so we check your home against its current rules before we quote (oil to heat pump conversion). The Mercer Island Fire Department regulates home heating oil tank decommissioning, which needs a permit and a certified decommissioner. We don't remove or decommission oil tanks, so you hire a decommissioner for that part.
Ducted, ductless and hybrid heat pumps
- Ducted heat pumps replace a furnace or air handler and use your existing ductwork.
- Ductless heat pumps mount on the wall, one indoor unit per zone. They suit homes heated by baseboards or wall heaters, additions, condos and upstairs rooms (ductless systems, baseboard to heat pump).
- Hybrid systems pair a ducted heat pump with a gas furnace, which takes over on the coldest nights (how dual fuel works, gas to heat pump conversion).
We are a Mitsubishi Electric Diamond Dealer, Carrier Factory Authorized Dealer, Lennox Premier Dealer and Quilt dealer, and we service all major brands.
Sizing for Mercer Island winters
Mercer Island is not listed in Washington's energy code climate table; the heating design temperature for nearby Bellevue is 24°F (WAC 51-11C-80100). We size every heat pump with an ACCA Manual J load calculation, room by room, rather than matching the old equipment, and we recommend cold-climate heat pumps or a hybrid system where your home needs more margin.
What a heat pump costs in Mercer Island
Your price depends on your home's heating and cooling needs, the add-ons you need, how many rooms the system serves and where it's installed. Get a price range in about 30 seconds with our free instant quote tool, then a technician confirms the exact price on a free site visit. More detail: heat pump cost guide.
Regional benchmark, not our price: Angi lists Seattle-area heat pump installations at about $6,667 to $13,852, averaging $10,218 (checked November 2026, Angi).
Financing through Salal Credit Union or Synchrony starts at $179/month* (financing).
*Financing through Salal Credit Union or Synchrony, subject to credit approval. Rates, terms and monthly payments depend on the amount financed, the plan and your credit. 0% interest options are available to qualifying customers. See lender for full terms.
Get a free estimateAn in-home visit and a written, upfront price before any work begins.
Permits on Mercer Island
The City of Mercer Island issues both permits: the mechanical permit through its Community Planning and Development department, and the electrical permit, because Mercer Island runs its own electrical inspections instead of Washington L&I (L&I city list). We pull the required permits for every installation and place the outdoor unit to keep it quiet for you and your neighbors.
Electrical panel check
A heat pump needs a dedicated circuit, and some older panels lack the space or capacity. We check your panel on the estimate visit, and our licensed electricians handle any upgrade (panel upgrades, WA Electrical Contractor Lic. #HOMECCA782DC).
Replacing an older heat pump in Mercer Island
Signs it is time: frequent repairs, weak heat in cold weather, rising bills, or a system that uses R-22 refrigerant. If your heat pump is out of warranty and centrally ducted, PSE's $1,500 upgrade rebate can help. Not sure? Read repair or replace a heat pump (heat pump replacement).
How installation works
- A free in-home estimate.
- A room-by-room Manual J load calculation and a look at your ducts and panel.
- Written options and prices, with the rebates each one qualifies for.
- We pull the City of Mercer Island mechanical and electrical permits.
- Install day, start-up and commissioning, and a walkthrough. Most heat pump installations take between 4 and 10 hours, depending on the system type and how many systems we install.
- Permit inspection, rebate paperwork and first-year maintenance included.
A 3-year Comfort Shield labor warranty on new installations, kept active with yearly maintenance. First-year maintenance is included. After that, a heat pump tune-up is $230, or $180 for Home Comfort Club members, per piece of equipment. Home Comfort Club members with a new system installed by Home Comfort Alliance get extended labor coverage for up to 5 years from installation. Home Comfort Club plans are $15 a month per trade or $30 a month for all three (membership plans).
A recent Mercer Island heat pump installation
In July 2026 we installed a new Carrier furnace and heat pump on Mercer Island as a hybrid system, tied into the home's existing ducts, gas line and venting, with a new pad and electrical disconnect for the outdoor unit and the old equipment hauled away. The heat pump handles the cooling and most of the heating, and PSE paid its $1,500 hybrid rebate.
Where we install on Mercer Island
We install heat pumps across Mercer Island (98040), from the North End through Mid-Island and the Town Center to the South End, from our Redmond branch. Nearby: heat pumps in Bellevue, heat pumps in Seattle and heat pumps in Issaquah.
Mercer Island heat pump installation FAQ
How much does heat pump installation cost on Mercer Island?
Your price depends on your home's heating and cooling needs, the add-ons you need, how many rooms the system serves and where it's installed. Get a price range in about 30 seconds with our free instant quote tool, then a technician confirms the exact price on a free site visit. For reference, Angi puts the Seattle-area average at $10,218, with a typical range of $6,667 to $13,852 (regional estimate, checked November 2026), before rebates.
Which heat pump rebates can I get on Mercer Island?
Mercer Island is part of Energy Smart Eastside, which takes $1,000 off a qualifying heat pump at the point of sale, with a bonus of up to $5,000 for income-qualified households installing fully electric systems. PSE supplies the island's electricity and gas and adds its own rebate based on how you heat today. Amounts checked November 2026.
Is Home Comfort Alliance an Energy Smart Eastside installer?
Yes. Home Comfort Alliance is on Energy Smart Eastside's network installer list, and the program's rebates are only available through those installers. We are also an approved PSE contractor (Trade Ally).
Which PSE rebate fits my home?
PSE pays $1,500 to replace electric resistance heat such as baseboards or an electric furnace, $1,500 to add a ducted heat pump to a PSE gas furnace, and $4,000 to income-qualified PSE gas customers who switch to a heat pump. A $2,400 income-based Efficiency Boost is also offered. We check which option pays you the most.
I heat with oil. Can I still get a rebate?
PSE's conversion rebate does not cover oil heat, and Seattle's Clean Heat rebate is for Seattle homes only. Energy Smart Eastside covers replacing an existing furnace, so we check your home against its rules before we quote.
What happens to my old oil tank?
The Mercer Island Fire Department regulates home heating oil tank decommissioning, and the work needs a permit and a certified decommissioner. We don't remove or decommission oil tanks, so you hire a decommissioner for that part.
Can I keep my gas furnace and add a heat pump?
Yes. A hybrid system runs on the heat pump most of the year and uses the furnace on the coldest days. PSE pays $1,500 for a ducted heat pump added to a PSE gas furnace, and Energy Smart Eastside pays $1,000 for a hybrid, but not the income bonus.
Do I need a permit for a heat pump on Mercer Island?
Yes. The City of Mercer Island issues both the mechanical permit and the electrical permit, because Mercer Island runs its own electrical inspections instead of Washington L&I. We pull the required permits for every installation.
Is there still a federal tax credit for heat pumps?
No. The federal 25C tax credit ended for heat pumps installed after December 31, 2025. Utility rebates are still available, and we check every program you qualify for.
Will a heat pump keep my home warm in a cold snap?
Yes, when it's sized right. The heating design temperature for nearby Bellevue is 24°F under the Washington State Energy Code. We size every system with a room-by-room Manual J load calculation.
How long does heat pump installation take?
Most heat pump installations take between 4 and 10 hours, depending on the system type and how many systems we install. If your panel needs work, our licensed electricians handle it (WA Electrical Contractor Lic. #HOMECCA782DC).
What warranty and maintenance come with a new heat pump?
A 3-year Comfort Shield labor warranty on new installations, kept active with yearly maintenance. First-year maintenance is included. After that, a heat pump tune-up is $230, or $180 for Home Comfort Club members, per piece of equipment. Home Comfort Club members with a new system installed by Home Comfort Alliance get extended labor coverage for up to 5 years from installation.
Sources: Energy Smart Eastside rebates and installer list (read November 2, 2026); PSE heat pump rebates (read November 2, 2026); Washington L&I city electrical list; WAC 51-11C-80100 design temperatures; Angi, Seattle heat pump cost.
Why Choose Home Comfort Alliance on Mercer Island?
Your Comfort is Our 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.
Ready to get started on Mercer Island?
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