San Francisco's foggy, damp winters make reliable heating important for every home. We provide furnace repair, wall heater service, and heat pump repair across all SF neighborhoods.
San Francisco's heating needs are unique. The city's persistent summer fog, marine layer humidity, and winter temperatures that routinely drop into the low 40s mean that a functional heating system isn't a luxury — it's essential. Yet SF's diverse housing stock presents challenges that few HVAC companies outside the city fully understand. We do.
SF HVAC Repair services the heating equipment found throughout San Francisco's housing stock: gas forced-air furnaces in post-war tract homes in the Excelsior, Visitacion Valley, and Ingleside; in-wall gas heaters (Empire, Williams, Comfort-Glow) in Victorian and Edwardian flats throughout the Castro, Haight-Ashbury, and Noe Valley; electric heat pumps increasingly common in newly remodeled SoMa lofts and Dogpatch townhomes; and ductless mini split heating in Victorian cottages without ductwork. We bring the parts, tools, and expertise to diagnose and repair the systems we service.
San Francisco's older housing stock creates specific failure modes our technicians diagnose daily. Wall heater thermocouples fail in the cold-and-damp cycling of SF winters. Cast-iron heat exchangers in pre-1970 furnaces develop stress cracks that pose carbon monoxide risks. Furnaces and heat pumps can develop worn blower motors, failed control boards, and thermostat communication faults after months without use. We've seen — and repaired — all of it.
Our diagnostic process starts with a $79 safety inspection and technical diagnosis. If we find a gas leak, cracked heat exchanger, or carbon monoxide risk, we explain the safety concern and the repair or replacement options. The diagnostic fee is waived with repair.
From Victorian wall heaters to modern heat pumps — these are the issues we fix most often in SF.
Could be a failed ignitor, a tripped high-limit switch, a faulty control board, a bad thermostat, or a gas supply issue. We test the full sequence of operation from thermostat call to burner ignition.
A furnace that cycles frequently is usually overheating — caused by a clogged filter, blocked registers, a failed blower motor, or a cracked heat exchanger. Short cycling also indicates the wrong furnace size for the home.
The blower runs but no warm air comes out. Most common causes: failed gas valve, cracked heat exchanger, failed ignitor, a failed blower motor, or a reversed/wired-incorrectly thermostat.
Extremely common in SF's Victorian stock. The thermocouple — a safety device that keeps the gas valve open when the pilot is lit — fails with age and damp cycling. A thermocouple replacement is a fast, affordable repair.
A brief burning smell when a furnace first turns on in fall is normal (burning off dust). A persistent burning smell, metallic odor, or smell of burning rubber indicates a motor, belt, or electrical issue requiring immediate attention.
A CO alarm with the heating system running is a life-safety situation. Evacuate immediately and call 911. After the all-clear, contact us to schedule a heat exchanger inspection — a cracked heat exchanger is a common source of CO in SF homes.
We serve all 28 San Francisco neighborhoods.