Furnace Installation & Replacement in Mercer Island, WA
A properly sized, high-efficiency furnace keeps every room warm through Pacific Northwest winters while cutting gas bills.
A furnace swap on Mercer Island has to account for access as much as the equipment — a shoreline Point home and a ridge-top house near Rotary Park rarely have the same venting or crawlspace conditions.
Symptoms we see every week in Mercer Island
- Furnace is 15+ years old or needs frequent repairs
- Uneven heating or cold spots across the home
- Rising winter gas bills from an aging unit
- Cracked heat exchanger or unreliable ignition
Spec'd to your Mercer Island home
We size every system to your actual demand — not a one-size guess. Here's what a typical furnace install includes:
| Efficiency | Up to 98% AFUE |
|---|---|
| Capacity | 40k–120k BTU |
| Fuel | Natural gas or propane |
| Lifespan | 15–20 years |
Furnace Installation in Mercer Island: what's different here
Elevation on the island runs from about 18 feet at the lakefront to almost 400 feet near the ridge, so equipment placement, condensate drainage and access change from block to block. Replacing a furnace in an older Mercer Island home usually means more than swapping the box. We check whether the original ducts in homes around East Seattle and the North End can handle the new unit's airflow, size the furnace with a load calculation, and often recommend a heat pump or dual-fuel system instead.
Permits and inspections
A furnace replacement needs a mechanical permit, and changes to the gas line are inspected too. Mechanical and plumbing permits in Mercer Island go through the City of Mercer Island Permit Center. When the work needs a permit, we pull it, schedule the inspection and leave you the paperwork.
Utilities and rebates
Mercer Island homes get electricity from PSE, and most have PSE natural gas. Mercer Island homeowners may qualify for utility, state or federal rebates. We point you to the current programs for your address before you sign.
Where we work in Mercer Island
Our job records show more than 80 completed jobs for Mercer Island customers across ZIP codes 98040. We take furnace installation calls in East Seattle, the North End, the South End, First Hill and the rest of Mercer Island.
Work we stand behind
10-year parts warranty, 2-year labor, and permit closure documentation provided.
Book this serviceGet a same-day quote from a real technician in Mercer Island.
Straight answers for homeowners in Mercer Island.
Who issues the permit for furnace installation in Mercer Island?
Mechanical and plumbing permits in Mercer Island go through the City of Mercer Island Permit Center. For furnace installation, we apply for the permit, book the inspection, meet the inspector on site, and give you the final sign-off for your records.
Should I replace my furnace with a heat pump in Mercer Island?
It depends on your ductwork, panel capacity and fuel costs. We give written options for a furnace, a heat pump and a dual-fuel system so you can compare. Mercer Island homeowners may qualify for utility, state or federal rebates. We point you to the current programs for your address before you sign.
Which Mercer Island neighborhoods do you cover?
Our job records show more than 80 completed jobs for Mercer Island customers across ZIP codes 98040. We take furnace installation calls in East Seattle, the North End, the South End, First Hill and the rest of Mercer Island. Call (425) 615-5000 for same-day service.
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