Furnace Repair in San Jose, CA
Facing a furnace failure on a freezing San Jose morning? Our techs diagnose and repair fast to restore your heat.
Furnace Repair in San Jose & the Bay Area
A furnace that won't ignite, keeps shutting off, or blows cold air needs attention fast — especially with kids or older family members in the house. Promax provides prompt furnace repair throughout San Jose and Santa Clara County, seven days a week. We troubleshoot igniters, flame sensors, gas valves, inducer motors, control boards, and thermostat faults on all major brands, and our vans carry the common parts to finish most repairs in one visit.
Every furnace repair includes a combustion analysis and carbon monoxide safety test at no extra charge. If we ever find a cracked heat exchanger — the one furnace problem that genuinely endangers your family — we document it with photos and walk you through every option, repair or replace, with honest numbers.
Furnace Repair, Done Right
Every furnace repair visit is built around three things: finding the real cause, fixing it with parts already on the truck, and getting a licensed technician to your door fast. Same-day service for no-cool, no-heat and no-hot-water calls, 7 days a week. Diagnostic fee waived with any repair.
- Fully stocked trucks carry parts for most repairs on the first visit
- We repair Bryant, Carrier, Trane and every other major brand
- Licensed, EPA-certified technicians on every call
- We stand behind our work — service and spare parts are both covered
What's Included With Furnace Repair
Every furnace repair visit covers the items below, and the scope and price are confirmed in writing before any work starts. When it's finished the technician walks you through what was done and what to watch for. We call back within one business hour, 7 AM – 10 PM.
- Igniter, flame sensor, gas valve, and inducer motor diagnostics
- Free combustion analysis and carbon monoxide safety test with every visit
- Upfront flat-rate pricing before any repair begins
- Common parts stocked on the truck for most major-brand repairs
- Photo documentation if a cracked heat exchanger is found
Signs You Need Furnace Repair
Each symptom below means a part is wearing out or already failing, and these problems rarely fix themselves. Waiting usually lets a small fault damage other components, which turns a modest repair into a larger one and raises the odds of a breakdown at the worst possible time. Call (669) 777-1997 or book online, and a technician will pinpoint the cause.
- The furnace won't ignite or keeps shutting off
- It's blowing cold air instead of heat
- Short-cycling — turning on and off repeatedly
- A burning smell, rattling, or banging when it runs
- The pilot light won't stay lit or keeps going out
- Your carbon monoxide detector has alarmed
Brands We Repair
Promax is a Bryant Factory Authorized Dealer, so Bryant equipment is repaired by technicians with factory-backed training. We repair every other major brand as well, whatever name is on your equipment. Our fully stocked trucks carry common parts for these brands, so most repairs are finished in a single visit.
Need furnace repair help in San Jose?
Related Services
Most furnace repair jobs touch one of these, and the same licensed Promax team handles all of them. Each page lists what's included, typical costs and the questions San Jose homeowners ask most. Not sure which you need? Call (669) 777-1997 and we'll point you to the right one.
Where We Work
Promax Service Group serves homes and businesses in San Jose, across Santa Clara County, and in nearby Peninsula and East Bay cities. Same-day service for no-cool, no-heat and no-hot-water calls, 7 days a week. Choose your city for local details, or call (669) 777-1997 to confirm we cover your address.
Frequently Asked Questions
Why does my furnace keep turning on and off?
Short-cycling usually traces to a dirty filter overheating the furnace, a failing flame sensor, a clogged condensate line on high-efficiency models, or an oversized system. It wastes gas and wears parts fast — most causes are inexpensive fixes when caught early.
Is a cracked heat exchanger dangerous?
Yes — it can allow carbon monoxide into your home's air supply, which is why we test CO on every heating visit. A confirmed crack means the furnace should be shut down; depending on age, the fix is either a warranty exchanger swap or replacement of the furnace.
Do you repair furnaces on weekends?
Yes — we operate 7 days a week, 7 AM to 10 PM, at the same rates. No 'weekend emergency' surcharge for getting your heat back on a Saturday night.
Is it safe to run my furnace while waiting for a repair?
If you smell gas, hear a CO alarm, or see soot around the unit, shut it off and call us immediately — those are safety issues, not comfort issues. Cold air blowing, short-cycling, or a furnace that won't start are usually safe to leave off until we arrive, since running it repeatedly can wear the parts further.
Do you carry parts for older furnace brands?
Yes — our vans stock common igniters, flame sensors, control boards, and blower motors across Bryant, Carrier, Trane, Lennox, Goodman, and other major brands. For obsolete parts on very old units, we'll source them fast or walk you through replacement options.