Published prices for a furnace service call in Ontario are $120–$250, and the most common repairs, an igniter or flame sensor, $80–$450. A blower motor is $300–$1,400, and a heat exchanger is the expensive one.
These figures come from Ontario HVAC contractors’ own price guides, one of them in Hamilton. After-hours and holiday calls cost more.
The service call
Most contractors charge for the diagnostic visit, and some credit it toward the repair if you go ahead.
Published service call prices
CAD · before HST · published prices
- Diagnostic / service callFrom a Hamilton HVAC contractor’s 2026 price guide
- $120–$250
- Diagnostic service call (waived if the repair goes ahead)From a Halton HVAC contractor’s 2026 price guide
- $120–$180
- After-hours, weekend or holiday premium, addedFrom a Hamilton HVAC contractor’s 2026 price guide
- $50–$150
- After-hours emergency diagnosticFrom a Halton HVAC contractor’s 2026 price guide
- $220–$280
Common repairs
A furnace that won’t light is usually the igniter or a dirty flame sensor, the cheapest fixes. Boards, inducer motors and gas valves are next.
Published repair prices
CAD · before HST · published prices
- Flame sensor cleaningFrom a Hamilton HVAC contractor’s 2026 price guide
- $80–$150
- Flame sensor replacementFrom a Hamilton HVAC contractor’s 2026 price guide
- $150–$300
- Igniter replacementFrom a Hamilton HVAC contractor’s 2026 price guide
- $150–$350
- Minor repair (igniter, sensor, fuse)From a GTA HVAC contractor’s price guide
- $150–$350
- Flame sensor or igniter replacementFrom a Halton HVAC contractor’s 2026 price guide
- $250–$450
- Control board replacementFrom a Hamilton HVAC contractor’s 2026 price guide
- $200–$600
- Draft inducer motorFrom a Hamilton HVAC contractor’s 2026 price guide
- $300–$600
- Gas valve replacementFrom a Hamilton HVAC contractor’s 2026 price guide
- $300–$750
- Blower motor repair or replacementFrom a Hamilton HVAC contractor’s 2026 price guide
- $300–$700
- Blower motor, standard (PSC)From a GTA HVAC contractor’s price guide
- $300–$700
- Blower motor, variable-speed (ECM)From a GTA HVAC contractor’s price guide
- $600–$1,100
- Blower motor replacementFrom a Halton HVAC contractor’s 2026 price guide
- $500–$1,400
- Heat exchanger replacementFrom a Hamilton HVAC contractor’s 2026 price guide
- $800–$1,500+
- Major repair (heat exchanger, board)From a GTA HVAC contractor’s price guide
- $400–$900
Repair or replace?
A cracked heat exchanger on an older furnace is often the point where replacing makes more sense than repairing. Compare the repair quote with the new furnace prices in the furnace cost guide.
Keep it from breaking
A yearly tune-up catches dirty flame sensors and worn parts before the first cold night.
Published tune-up prices
CAD · before HST · published prices
- Furnace, AC or heat pump tune-upFrom a GTA HVAC contractor’s price guide
- $175
- Annual furnace tune-upFrom a Halton HVAC contractor’s 2026 price guide
- $140–$220
- Annual AC tune-upFrom a Halton HVAC contractor’s 2026 price guide
- $130–$200
Questions people ask
How much does furnace repair cost in Ontario?
Published prices: $120–$250 for the service call, $80–$450 for an igniter or flame sensor, $300–$1,400 for a blower motor, before HST.
Is it worth repairing an old furnace?
A small repair usually is. A major one, like a heat exchanger, on a furnace near the end of its life often isn’t; compare it with the cost of a new furnace.
Where these prices come from
These figures are from Ontario HVAC contractors’ own published price guides, one of them in Hamilton, checked October 23, 2026. We don’t name them: we’re a referral service and don’t promote individual contractors. They’re ranges, not quotes, before HST and before rebates. Rebates are from the Home Renovation Savings Program’s own page, linked above.