What Does Furnace Repair Cost?
Professional furnace repair costs $150 to $2,500, averaging around $450 for most residential service calls. The spread reflects the difference between replacing a $30 igniter and addressing a cracked heat exchanger that may justify full furnace replacement. The specific problem, the part, and the labor determine where your repair lands.
Diagnostic or Service Call: $75 to $200
The diagnostic or service call fee covers the technician’s visit, system assessment, and fault identification, which on a furnace usually means testing electrical components, safety controls, and the ignition sequence. Many HVAC companies credit the fee toward the repair if you authorize the work, so it is often part of the repair cost rather than an addition to it. Confirm that before you commit. (For more on this, see What Affects Furnace Repair Cost?.)
Common Repairs: $150 to $700
The components that fail most often in residential gas furnaces account for the majority of service calls, and they all land in this band.
| Cost Factor | Typical Range | Notes |
|---|---|---|
| Igniter replacement | $150 to $300 | The most common gas furnace repair. The igniter lights the burners each time the furnace fires and wears out with heating cycles. |
| Flame sensor cleaning or replacement | $75 to $250 | The sensor confirms the flame is lit; it accumulates residue and stops detecting reliably. |
| Blower motor replacement | $350 to $700 | The motor that circulates heated air through the ductwork. |
| Control board replacement | $300 to $700 | The board that sequences ignition, safety checks, and blower operation. |
| Gas valve replacement | $250 to $600 | Controls gas flow to the burners. |
Most of these take 1 to 3 hours and restore heat in a single visit. Furnace repair costs cluster this way for a reason: the large majority of service calls involve a handful of components that fail routinely with age and use — igniters that crack after years of heating cycles, flame sensors that accumulate residue, capacitors and blower motors that wear, and control components that eventually give out. The parts are reasonably priced and the labor, while it demands skill and safety knowledge, fits in one visit. That is why the average repair sits well below the top of the range: most problems are ordinary component failures rather than catastrophic ones. (For more on this, see How to Budget and Pay for Furnace Repair.)
Major Component Replacement: $1,000 to $2,500
Heat exchanger replacement is the most expensive furnace repair and the one most closely tied to the replacement decision. The heat exchanger separates combustion gases from the air circulated through the home. A crack lets those gases, including carbon monoxide, mix with supply air — a safety issue that must be addressed, not deferred. Replacement costs $1,000 to $2,500 depending on the furnace model and the labor involved, and it typically takes 4 to 8 hours or longer because the furnace has to be extensively disassembled. On a furnace over 15 years old, replacement is often the better financial and safety decision. (For more on this, see Signs Your Furnace Needs Repair vs. Replacement.)
Furnace Repair Cost at a Glance
| Repair | Cost |
|---|---|
| Diagnostic or service call | $75 to $200, often credited |
| Flame sensor cleaning or replacement | $75 to $250 |
| Igniter replacement | $150 to $300 |
| Gas valve replacement | $250 to $600 |
| Control board replacement | $300 to $700 |
| Blower motor replacement | $350 to $700 |
| Heat exchanger replacement | $1,000 to $2,500 |
| Overall range | $150 to $2,500, averaging $450 |
What Else Affects the Cost
Beyond the failed part itself, the labor matters: some repairs are quick, others require significant disassembly. The furnace’s age, type, and fuel shift the price too, since gas, electric, and oil furnaces differ and older or specialized units can have pricier, harder-to-find parts. If the technician finds additional safety issues, correcting them adds work. And emergency or after-hours service costs more, which matters with furnaces because they tend to fail in cold weather, when response times also stretch under peak demand.
When Repair Stops Making Sense
A workable rule: multiply the repair cost by the age of the furnace in years. If the result exceeds $5,000, lean toward replacement. A $1,500 heat exchanger on a 12-year-old furnace comes to $18,000 — replace it. A $400 blower motor on a 10-year-old furnace comes to $4,000 — repair it.
Replace regardless of that math when the heat exchanger is cracked on a furnace over 15 years old, since you are combining a safety problem with a unit near the end of its life. Repeated failures across different components suggest overall system deterioration, and a furnace paired with an R-22 air conditioning system faces refrigerant phase-out that affects the whole package. Spending thousands on a major component in an aging unit rarely represents good value against a new, efficient, warrantied system. ENERGY STAR publishes certified efficiency ratings for heating and cooling equipment, which is the cleanest way to compare models.
Getting an Accurate Price
Because the cost depends entirely on what failed, an accurate number comes from a diagnosis, not a symptom description. Most common repairs finish in 1 to 2 hours; blower motor and control board work takes 2 to 4 hours; a heat exchanger takes 4 to 8 hours or more.
Treat the ranges here as planning benchmarks rather than fixed prices; what you pay depends on your local labor market, current parts pricing, and the scope the technician confirms on site. On anything at the major-component end, get at least two written quotes on the same defined scope. Wide variation between them usually reflects a different diagnosis, different parts quality, or different labor warranty terms rather than simple price competition.
Ask whether the diagnostic fee is credited, what the labor warranty covers, and whether the quoted part is in stock. On any major component quote, get a replacement quote alongside the repair quote so you are comparing the two decisions on the same day, with the same information.
Frequently Asked Questions
Furnace repair runs $150 to $2,500, averaging $450. The diagnostic call is $75 to $200 and is often credited, common repairs like an igniter, flame sensor, or blower motor run $150 to $700, and a major component like the heat exchanger runs $1,000 to $2,500.
$75 to $200. The technician comes out, tests electrical components, safety controls, and the ignition sequence, identifies the fault, and provides a repair quote. Many companies credit the fee toward the repair if you proceed, so confirm the policy when you book.
Igniter replacement, at $150 to $300 including labor. The igniter lights the gas burners each time the furnace fires and is a consumable component that typically lasts 5 to 10 years. When it fails, the furnace tries to start, cycles off without lighting, and throws an error code.
Yes. The heat exchanger separates combustion gases from the air circulated through your home, and a crack lets carbon monoxide mix with the supply air. CO is colorless, odorless, and potentially fatal. If a technician identifies a crack, do not operate the furnace until the exchanger or the furnace is replaced, and keep CO detectors on every floor.
When the repair cost multiplied by the furnace's age in years exceeds $5,000. A $1,500 heat exchanger on a 12-year-old furnace equals $18,000, so replace it; a $400 blower motor on a 10-year-old furnace equals $4,000, so repair it. Also replace when the heat exchanger is cracked on a furnace over 15 years old or when failures keep repeating.
The component itself costs substantially more than routine parts, and installing it requires extensive disassembly of the furnace, which is why the job runs $1,000 to $2,500 and takes 4 to 8 hours or longer. Because a crack is also a combustion safety issue, the finding usually opens a replacement conversation rather than a repair one.
One to 2 hours for most common repairs such as an igniter, flame sensor, or minor electrical component. Two to 4 hours for a blower motor or control board. Heat exchanger replacement takes 4 to 8 hours or longer depending on the furnace configuration. Emergency calls during cold snaps may have longer response times.
The part that failed, how much disassembly the repair requires, and the furnace's age, type, and fuel -- gas, electric, and oil units differ, and older or specialized models have pricier, harder-to-find parts. Additional safety issues found during service add work, and emergency or after-hours calls cost more.