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Furnace burner and igniter being servicedFormerly Adam & Sam Brothers Repair

Mill Creek · Gas furnaces & dual fuel

Mill Creek furnaces, repaired before replaced

Most Mill Creek homes went up after 1980, and close to six in ten heat with gas. That puts a lot of furnaces in their late twenties or thirties right now. We repair what can be repaired and quote the rest plainly.

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Gas heat
About 57% of Mill Creek homes; 43% electric
Built 1980–99
About 47% of homes; another 38% since 2000
Drive time
15–19 minutes off-peak by I-5 and 164th St SW
  • $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.

Mill Creek started as a master-planned community around a private golf course, with the first homes sold in 1975 and 1976 and an original plat of 21 subdivisions named after trees. The city incorporated in 1983, annexed Thomas Lake in 2005, and added apartments and townhomes at East Gateway and The Farm more recently. Almost nothing here predates 1960. What that means for heating is a city full of second-generation gas furnaces, a growing number of condensing units, and plenty of homes where a heat pump has already been bolted onto the furnace for dual-fuel operation. Jackson High School and the Town Center are our usual reference points, and SR 527 is the road that decides our arrival time.

Our approach in Mill Creek follows the same rule as everywhere: diagnose first, write one price, repair with your approval. The difference is what we find. Builder-installed furnaces from the 1980s and 1990s are largely gone, and their replacements are now between fifteen and twenty-five years old, which is when inducer motors, control boards and blower motors start to tire. Common furnace parts ride on our vans, so many of those failures are fixed on the first visit. When one is not, we order the part the same day and tell you when we will be back.

What Mill Creek furnace calls usually turn out to be

  • Furnace in the garage starts, then locks out after three tries

    Likely cause
    Weak flame sensor, worn hot surface igniter or a failing gas valve
    What we do
    Pull the stored codes, test each step of ignition and replace the part that fails

  • Water around the furnace base in the garage

    Likely cause
    Condensate trap clogged, drain hose cracked or condensate pump failed
    What we do
    Clean the trap, replace damaged hose, test or replace the pump

  • Loud hum or vibration before the burners light

    Likely cause
    Inducer motor bearings wearing out
    What we do
    Replace the inducer assembly and recheck the draft and pressure switch

  • Heat pump runs, but the furnace takes over too often

    Likely cause
    Dual-fuel balance point set wrong, or a fault in the heat pump
    What we do
    Check the thermostat's dual-fuel settings and test the outdoor unit's charge and controls

  • Blower runs slow or the house feels drafty and lukewarm

    Likely cause
    Failing blower motor or capacitor, or a clogged filter
    What we do
    Measure motor draw and capacitor value, change the filter, and replace the motor if needed

  • Gas odor near the furnace or water heater

    Likely cause
    Possible gas leak
    What we do
    Leave the house; once outside, call PSE at 1-888-225-5773 or 911 and wait for them to clear it

Mill Creek, Silver Firs and Mill Creek East

Inside the original plat, many homes put the furnace in the garage or a crawlspace, which makes them easy to reach but exposes them to cold air and, in garages, to dust and road grime. Filters clog faster there, and a starved furnace runs hot. In the townhomes and apartments around East Gateway and Mill Creek Town Center, electric furnaces or air handlers in closets are more common, and their trouble spots are elements and sequencers rather than burners. We see both on the same afternoon, and we stock the van for both. Because the tree-named subdivisions were built in phases, neighbors frequently own furnaces of similar age, and a street where one furnace has failed often has a few others close behind. Homes around the golf course at the heart of the original plat date to the late 1970s, which makes them the most likely in town to be on a third furnace.

Just outside the city, Mill Creek East and Silver Firs are even more gas-heavy, at about 64% and 71% of homes respectively; Silver Firs has the highest gas share of any area we checked. Mill Creek East is also young, with about 59% of its homes built since 2000, so its furnaces are often 95% condensing models with ECM blowers and stored fault codes. We treat those addresses as part of our Mill Creek route, about 19 to 27 minutes from the shop depending on which end you are on. Martha Lake, on the western side toward Lynnwood, rounds out the route, and its blend of older and post-2000 homes looks much like Mill Creek's own.

Mill Creek buys its power from Snohomish County PUD, and PSE pipes in the gas. Many owners here added a heat pump to an existing furnace in the last few years, especially after the June 2021 heat wave, when Mill Creek reportedly saw temperatures above 105°F. Those dual-fuel systems need both halves working, and we service them as one system. If you are considering adding one, we check which PUD or PSE programs apply before we price it.

Our team after a furnace installation

Mill Creek furnace repair and install prices

Furnace repair in Mill Creek starts at $285. With so many second-generation furnaces now fifteen to twenty-five years old, inducer motors and control boards make up a large share of our calls here, and both sit toward the upper end of the category. If you want to keep your gas furnace and add a heat pump for dual fuel, an outdoor unit starts at $5,250, equipment and installation included. These are starting prices for south Snohomish County rather than a quote; the actual number goes on your written estimate after we diagnose, and the replacement site visit and quote are no charge.

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 or replace a Mill Creek furnace?

A typical Mill Creek furnace today is an 80% or 90%-plus gas unit from the late 1990s or 2000s, now fifteen to twenty-five years old. For those, a failed igniter, flame sensor or pressure switch is a repair every time. An inducer or control board on a furnace past twenty is closer, and we write both prices so you can see the gap. A cracked heat exchanger means replacement, and we show you the evidence first. If you do replace, a 95% furnace is the forward-looking pick, since the federal rule now on the books phases new 80% indoor gas furnaces out of production in late 2028. In a garage installation, a 95% unit's PVC venting and condensate drain are usually simple to route. Many Mill Creek owners also pair the new furnace with a heat pump, since a dual-fuel setup handles mild days on electricity and adds cooling.

Common questions

Do you serve Silver Firs and Mill Creek East?

Yes. Both are part of our Mill Creek route. Mill Creek East is roughly 19 to 24 minutes from our shop off-peak, and Silver Firs about 22 to 27. Both areas lean heavily on gas heat, and many homes there have newer condensing furnaces. Pricing is the same as inside city limits, with no distance charge.

Can you fix my dual-fuel system if the heat pump side quits?

Yes. We work on both halves: the gas furnace and the heat pump, including refrigerant work done by our own technicians under EPA Section 608 rules. Often the issue is a thermostat setting or a control fault rather than a failed component, and we check those first.

Why does my garage furnace go through filters so fast?

Garages are dusty, and a furnace there draws in more debris than one in a hallway closet. Check the filter monthly in winter and replace it when it looks gray. A clogged filter makes the furnace run hot, trip its limit switch and wear out its blower motor sooner.

Should I replace my 80% furnace with another 80% model?

You can, and it is still legal today. But the federal standard as now written moves new gas furnaces of this type to 95% efficiency starting in late 2028, and a 95% unit uses less gas. In most Mill Creek garages, the PVC vent and condensate drain are easy to add, so we quote both options for comparison.

The garage smells like gas. What do I do?

Get out of the house right away, and do not use the door opener, light switches or thermostat on the way. Phone PSE at 1-888-225-5773, or 911, once you are clear of the building. Leave the furnace alone until PSE has made the line safe; after that, we can inspect it and write up whatever repair it needs.

Talk to Adam & Sam

Mill Creek homeowners can reach us by phone at (425) 570-9520, or book on our site to knock up to $18 off the repair. An approved repair absorbs the $85 diagnostic, and the trip to size a new furnace or a dual-fuel 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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