Catch the problem before it catches you
Most Fresno homeowners ignore early warning signs until the furnace fails completely — usually on the coldest night of the year.
Blowing cold or room-temperature air
Most common causes are a failed igniter, a fouled flame sensor, or a gas supply issue — all of which get worse the longer the system runs undiagnosed.
Short cycling
Furnace ignites, runs briefly, then shuts off before the home reaches temperature — usually a tripped high-limit switch, a cracked heat exchanger, or a blocked flue. Never normal.
Banging, rattling, or squealing
Banging at startup indicates delayed ignition. Rattling suggests a loose component. Squealing is a blower motor bearing. Every one gets worse with every cycle.
Yellow or orange burner flame
A healthy gas burner produces a steady blue flame. Yellow or orange indicates incomplete combustion, which means carbon monoxide may be present. Turn the furnace off and call immediately.
Gas bills spiking unexpectedly
A furnace losing efficiency runs longer to produce the same heat output. A significant bill increase with no change in usage points to a system working harder than it should.
Furnace over 15 years old
Heat exchangers in older furnaces are at elevated risk of cracking, and components degrade over time. Diagnosis now costs far less than an emergency replacement in January.
Fresno furnace repair — actual numbers
No “come to your house to see the price” games. Most furnace repairs range from $150 to $1,500 depending on the failed component. Your exact price is locked in writing after we diagnose the system.
Typical Repairs
On-site inspection, full system test, written quote. Igniter replacement: $150-$300. Flame sensor cleaning: $80-$150. Control board: $400-$900. Overall typical range: $180-$650.
Full Replacement — $0 Down
If your system is 12+ years old or the heat exchanger’s cracked, replacement often beats repair. From $89/month, 144-month terms, 4.99% APR.
Four reasons Fresno homeowners call us first
Fresno-local W-2 techs
We don’t subcontract. Every tech who pulls up works for Grandmark, passed our background check, and has served Fresno homes for years.
Carbon monoxide safety, every call
A cracked heat exchanger can allow CO into living spaces — a life-safety issue with no symptoms until it’s too late. We assess CO risk on every furnace call as standard procedure.
$0 down, 0% interest for 18 months
If the repair turns into a replacement, you’re not stuck. Same-day approval, no hard credit pull, no early payoff penalty.
Fix it or you don’t pay
Same problem comes back after we repair it — we return at no charge. No argument, no invoice. Applies to every heating repair across Fresno County.
What Fresno homeowners say
4.8 stars across 1,200+ verified Google reviews — Fresno, Clovis, Madera, Sanger, Selma, and surrounding Fresno County cities.
Had my furnace “repaired” twice by two other Fresno HVAC companies and it kept failing. Grandmark found the real cause on video — a fouled flame sensor and a failing inducer motor nobody had checked.
Furnace quit on the coldest night of the year. Grandmark came out same day, diagnosed it on video, and had the heat back on within two hours. Every other company told me the earliest was three days out.
They replaced our old furnace and checked the heat exchanger for carbon monoxide at the same time. House heats up twice as fast now and I have video proof of every step.
We’ll respond in 20 minutes or less
Tell us your symptoms and we’ll get a tech on the way. During business hours, that’s typically within 20 minutes.
Furnace repair FAQ
Why is my furnace blowing cold air?
The most common causes are a failed igniter, a fouled flame sensor, a tripped high-limit safety switch, a failed control board, or a gas supply issue. Each has a different cause and a different repair, which is why proper diagnosis before replacing parts matters. We document the diagnosis on video before quoting any repair.
Do you check for carbon monoxide when servicing a furnace?
Yes — on every single furnace call, as standard procedure. A cracked heat exchanger can allow carbon monoxide into living spaces, a life-safety issue with no symptoms until it’s too late. CO safety assessment is not optional and not an add-on charge.
What if the same problem comes back after you repair it?
We make it right at no charge. If we diagnose your heating repair and fix it, and the same issue returns, we come back and handle it — no argument, no invoice. That guarantee applies to every residential and commercial heating repair we complete across Fresno County.
Do you repair heat pumps as well as gas furnaces?
Yes. We service both gas furnaces and heat pump systems across Fresno County. Heat pump heating diagnosis requires different knowledge than furnace diagnosis — we assess reversing valve function, defrost cycle performance, refrigerant charge in heating mode, and auxiliary heat sequencing.
How quickly can you get to my home?
Most non-emergency service calls are dispatched same-day. For true no-heat emergencies on cold nights or any suspected carbon monoxide issue, we prioritize same-day response, typically within 2-4 hours. Call (559) 245-1485 for current availability.
How much does furnace repair cost in Fresno?
Most furnace repairs range from $150 to $1,500 depending on the failed component. An igniter replacement typically runs $150-$300, a flame sensor cleaning runs $80-$150, a control board replacement runs $400-$900, and a heat exchanger repair can run $1,000-$1,500 — at which point replacement is often the better financial decision. We provide a written quote before any work begins.
Heating repair across Fresno County & 11 surrounding cities
Licensed HVAC crews dispatched from our 3681 W McKinley Ave office. Same-day availability in most ZIP codes.
Stop freezing. Start calling.
Licensed Fresno techs on standby. Same-day diagnostics. Written quote before a wrench turns. Fix it or you don’t pay.