TL;DR. Our diagnostic fee is $129 and is credited toward repair work over $400. Common repairs: flame sensor $175-$300, igniter $230-$420, blower motor $560-$1,380, control board $520-$1,100, heat exchanger $2,200-$4,200. Replace instead of repair if the cost approaches 50% of replacement on a 15+ year old furnace.
Direct answer, common furnace repair costs
| Repair | Parts | Labor | Total |
|---|---|---|---|
| Flame sensor clean or replace | $25-$80 | $150-$220 | $175-$300 |
| Hot surface igniter replacement | $80-$180 | $150-$240 | $230-$420 |
| Thermocouple (older furnaces) | $30-$80 | $150-$200 | $180-$280 |
| Thermostat replacement | $150-$350 | $150-$250 | $300-$600 |
| Capacitor (run or start) | $40-$120 | $180-$240 | $220-$360 |
| Blower motor (single-speed) | $280-$520 | $280-$420 | $560-$940 |
| Blower motor (ECM variable-speed) | $480-$900 | $320-$480 | $800-$1,380 |
| Inducer motor | $250-$480 | $240-$380 | $490-$860 |
| Pressure switch | $80-$220 | $180-$280 | $260-$500 |
| Gas valve | $180-$420 | $240-$380 | $420-$800 |
| Limit switch | $80-$200 | $180-$280 | $260-$480 |
| Control board | $280-$680 | $240-$420 | $520-$1,100 |
| Heat exchanger | $800-$1,800 | $1,400-$2,400 | $2,200-$4,200 |
| Full burner assembly | $400-$900 | $400-$600 | $800-$1,500 |
Our diagnostic fee is $129 and is credited toward any repair work over $400. Most repairs complete same-day if the parts are common (flame sensor, igniter, capacitor, thermostat). Less-common parts (specific model control boards, premium ECM motors) sometimes require 2 to 5 days to source.
What drives furnace repair price
Three variables.
Part availability. Common parts (flame sensors, igniters, capacitors) are in our truck. Specific-model parts (some Bosch and Lennox proprietary components) require ordering. Same-day vs next-week.
Age of the system. Pre-2010 furnaces sometimes need parts that are no longer manufactured. We can find substitutes, but it adds labor time. Post-2015 furnaces have parts in stock at every supply house in the region.
Brand. Carrier and Trane have the broadest parts network. Bryant, Goodman, Rheem are similar. Lennox sometimes requires Lennox-specific parts. Bosch, similar. Mitsubishi and Mr. Cool have narrower distribution.
The repair vs replace decision
Industry rule of thumb: if the repair cost approaches 50% of replacement cost, replace. For most Seattle furnaces in 2026:
- Replacement cost (mid-tier 95% AFUE): $7,500 to $9,500
- 50% threshold: $3,750 to $4,750
- Repairs near this threshold: heat exchanger, full burner assembly, multiple-component failures
For older furnaces (15+ years), use a lower threshold (30% of replacement). The remaining life on the asset doesn’t justify $2,500 in repairs.
See our full repair vs replace guide for the decision math.
Common Seattle repair scenarios
Three typical repair scenarios.
Scenario 1: 8-year-old Carrier 95% AFUE, flame sensor
- Diagnostic: 30 minutes
- Issue: Flame sensor coated with carbon deposit
- Action: Clean with fine steel wool, reinstall
- Total: $129 diagnostic + $0 (clean only, no part)
Scenario 2: 12-year-old Lennox, blower motor
- Diagnostic: 45 minutes
- Issue: Failed ECM variable-speed blower motor
- Action: Replace with OEM Lennox part (in stock at supply house, available next day)
- Total: $1,180 (parts + labor, $129 diagnostic credited)
Scenario 3: 22-year-old Goodman, heat exchanger crack
- Diagnostic: 90 minutes (CO test, visual inspection)
- Issue: Visible heat exchanger crack
- Action: Recommended replacement (not repair) due to age and CO safety
- Total: $129 diagnostic (full credit toward replacement project quoted at $8,400)
Why our diagnostic fee is $129 specifically
Industry diagnostic fees range from $79 to $189 in Seattle. $129 is in the middle. Three reasons we picked it:
It covers actual time. A real diagnostic on a furnace takes 30 to 90 minutes. A $79 diagnostic incentivizes the tech to spend 15 minutes and recommend replacement to make up the labor. $129 lets us spend the full 60+ minutes diagnosing properly.
It’s creditable. Customers proceeding with repair work over $400 get the $129 credited. The diagnostic is effectively free for customers we actually do repair work for.
It’s transparent. Some contractors quote “free diagnostic” then charge $349 for the first 30 minutes of repair labor (which is the diagnostic in another wrapper). We don’t.
Schedule a diagnostic
Call (206) 200-9134. Same-day diagnostic Mon-Sun, 7 AM to 8 PM. $129 diagnostic fee, credited toward repair work over $400.