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Technician beside a furnace in a utility roomFormerly Adam & Sam Brothers Repair

Shoreline · Furnace service

Shoreline furnace repair and replacement planning

Shoreline's heat splits between gas and electric furnaces, many sitting in the basements of 1950s ramblers. We repair both kinds, quote replacements when a furnace is finished, and price a heat pump alongside them, 8–11 minutes from our shop.

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Electric heat
About 51% of homes heat with electricity, per Census estimates
Built pre-1960
About 35% of homes, most from the 1950s boom
Utilities
Seattle City Light power citywide; PSE gas in most areas
  • $85 diagnosticBecomes part of the repair price when you say yes. If you pass on the repair, that visit is all you pay.
  • Up to $18 offAny repair requested through the online form. The diagnostic itself is never reduced.
  • No-charge site visitInstalls are quoted in writing, equipment and installation work in one number.

From 1950 to 1957, Shoreline was the fastest-growing corner of the Seattle metro, and those post-war houses still set the tone in Ridgecrest, Briarcrest, Meridian Park and much of the rest of the city. Plenty of them still keep the furnace in the basement, often the second or third unit to sit on the same spot. Census estimates put slightly more Shoreline homes on electric heat than on gas, so that basement may hold either kind. The Lynnwood Link stations at 148th and 185th have since brought new townhomes and apartments to the city, and many of those arrive with electric heat or heat pumps, which widens the mix of equipment we see on a single street.

So our Shoreline furnace calls come in three flavors. Gas furnaces get igniter, flame sensor, inducer and board repairs. Electric furnaces get sequencer and element work. The third group is the furnace that has simply run out of years: there, what we bring is a replacement plan with a written price attached, usually with a heat pump priced beside it. In every case the diagnosis comes first, and you see the number before a single part is changed.

Common Shoreline furnace problems

  • Furnace dead after a windstorm outage

    Likely cause
    Control board or transformer hit by a surge when power came back
    What we do
    Read the board's status light, test the transformer and replace whichever failed

  • Gas furnace tries three times, then locks out

    Likely cause
    Igniter, flame sensor or gas valve failing
    What we do
    Pull the fault history, test each part in the ignition sequence, and replace the one that fails

  • Basement furnace short-cycles in the coldest week

    Likely cause
    Loaded filter, a crushed return, or a weak limit switch
    What we do
    Restore airflow first, then test the limit and replace it if it opens below its rating

  • Electric furnace heats some rooms but not others

    Likely cause
    An element out, or duct runs pulled loose in the basement or crawlspace
    What we do
    Meter each element, then inspect the trunk and the take-offs we can reach

  • Blower hums but will not spin

    Likely cause
    Failed run capacitor or a seized PSC motor
    What we do
    Test and replace the capacitor; if the motor has seized, fit a matched replacement

  • Gas smell in the basement

    Likely cause
    A leak at the furnace, water heater or piping
    What we do
    Walk out of the house, then call PSE at 1-888-225-5773 or 911; do not go back to shut anything off

Post-war basements, gas mains and spring snow

When a furnace reaches the end, a Shoreline owner usually has three paths. If PSE gas runs on your street, which covers most of the city, a gas furnace can go into the same basement corner with venting sized for it. If there is no gas, an electric furnace is the simplest swap, though the most expensive to run on City Light power. The third path, worth pricing next to the other two, is a heat pump, either alone or paired with a small electric furnace as backup. Moving an all-electric house to gas means a new PSE service line and a vent route, which we put in the plan rather than leave as a surprise. PSE's 136 miles of main reach most neighborhoods but not every street, so we confirm gas is available before quoting a gas furnace.

Post-war ductwork in Shoreline basements tends to be simple: one trunk, short branch runs, and returns laid out for a much older furnace. When modern equipment lands on those ducts, airflow is the first thing to check. From Richmond Beach and Innis Arden on the west side to Ridgecrest and North City east of I-5, we measure temperature rise and static pressure on every replacement, because those two readings decide how long a new furnace lasts. On older repairs we also look at the flue connector and the draft at the water heater, since a basement shared by two gas appliances is only as safe as its venting. Along the Aurora corridor near Shoreline Community College, apartments lean toward electric heat, and those repairs look more like elements and relays than burners.

Shoreline also sits in the Convergence Zone. On April 18, 2008, one of its bands left about 3.5 inches of snow here, in the middle of spring, and cold, wet snaps like that are when a weak igniter finally quits. The November 2024 bomb cyclone left about 43,000 City Light customers without power at one point, and every furnace on those streets sat dark until the lines came back. Every Shoreline neighborhood gets its electricity from Seattle City Light, and PSE carries gas to most areas. When a heat pump is on the table, we check which City Light or local programs might apply to your house and keep any rebate talk to what is confirmed.

Furnace burner and igniter being serviced

Furnace pricing for Shoreline homes

Furnace repair in Shoreline starts at $285. In the post-war basements, gas furnace calls often trace back to a limit switch tripping on a starved return or a blower motor that has run for decades. A like-for-like 80% gas furnace replacement starts at $4,750, equipment and installation included; switching an electric house to gas adds venting and a PSE service line, and the written quote lists each of those separately. All of these are starting prices for the area, not a quote. Your number comes on the written estimate after diagnosis, and the replacement site visit and quote are at no cost.

See all prices

  • Flame sensor cleaning or replacementfrom $285
  • Furnace igniterfrom $285
  • Limit switchfrom $285
  • Pressure switchfrom $285
  • Sequencer or heat relayfrom $285
  • Electric heat strip / elementfrom $285
  • Furnace or air handler control boardfrom $425
  • Gas valvefrom $425
  • Blower motor (standard PSC)from $475
  • Inducer motorfrom $550
  • Blower motor (ECM / variable speed)from $850
  • Diagnostic visit$85, included in the repair

Starting prices for the north Seattle area, 2026. The $85 diagnostic is included in any repair you approve, and the exact price is in the written estimate before work starts.

System, installed

  • Gas furnace, 80% AFUEfrom $4,750
  • Gas furnace, 95%+ AFUEfrom $6,500
  • Electric furnacefrom $4,500
  • Heat pump outdoor unit onlyfrom $5,250

Install prices start here, equipment and installation included, before any utility program. Multi-zone systems are priced after a visit. We do not charge for the site visit or the written quote.

Repair, replace, or add a heat pump

For a gas or electric furnace in a Shoreline basement, age and condition drive the call. Basements give us room to work, so repairs are rarely complicated by access, and a furnace under fifteen years old with a failed igniter, limit or capacitor should simply be fixed. Past twenty years, a major part such as a heat exchanger, an inducer or a variable-speed blower changes the math, and we write both prices for you. For an older furnace that still runs reliably, our advice is about timing: plan the replacement in a dry month instead of during a cold snap, when choices narrow and waits get longer. Many Shoreline owners in that position price a heat pump alongside a gas furnace, since a heat pump also adds the summer cooling those post-war houses were never built with.

Common questions

My furnace is old. What are my replacement options?

Usually three. We look at the house, tell you whether PSE gas is likely available on your street, and write prices for a gas furnace, an electric furnace or a heat pump. All three fit a post-war basement, so the choice comes down to running cost on City Light power, gas availability and whether you want summer cooling.

Which Shoreline neighborhoods do you serve?

All fourteen, from Richmond Beach and Innis Arden on the Sound to Ballinger, North City and Briarcrest on the east side. Off-peak, most addresses are eight to eleven minutes from our shop by I-5 or SR 99. Same-day visits are common when you reach us early in the day, Monday through Saturday.

Why is one bedroom always cold in my 1950s house?

Usually it is the ducts rather than the furnace. The far room may have a long run, a crushed flexible section or a disconnected boot in the crawlspace or basement. We check the furnace first, then trace the ducts we can reach and tell you what can be fixed now and what belongs in a bigger project.

Do heat pumps keep up in Shoreline winters?

Yes. Shoreline's marine climate keeps most winter hours in a range where a modern heat pump runs efficiently, and backup heat covers the rare hard freeze. Our technicians do the refrigerant work in-house under EPA Section 608 rules. We check which Seattle City Light or local programs apply and leave dollar amounts to the program itself.

What if the basement smells like gas?

Get out of the house before anything else, skipping lights and the thermostat. Once outside, call PSE at 1-888-225-5773 or 911; they will shut off and check the gas. After their all-clear, call us to inspect the furnace and its connections and to write up any repair it needs.

Talk to Adam & Sam

Call (425) 570-9520 to set up Shoreline furnace service, or schedule online and take up to $18 off the repair. The $85 diagnostic counts toward the repair when you approve it, and the visit to quote a replacement or a heat pump costs nothing.

Call (425) 570-9520Book online

From Sam’s repair notes

Schedule a repair

Request a visit from Adam & Sam

Send the basics and we call you back with an arrival window, most days the same morning.

  • $85 diagnostic Becomes part of the repair price when you say yes. If you pass on the repair, that visit is all you pay.
  • Up to $18 off Any repair requested through the online form. The diagnostic itself is never reduced.
  • $10 off A second appliance’s diagnostic when we check it during the same trip.

Requests sent from this form get up to $18 off the repair. The $85 diagnostic stays the same and is folded into any repair you approve.

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