Fast, Reliable Heating & Furnace Across San Francisco
Heating repair in San Francisco runs $175–$825 for most wall furnace and gas furnace issues, with same-day service available across the city. Our technicians are familiar with the unique challenges of San Francisco’s pre-1920 housing stock, from Tenderloin Edwardians to Mission District Victorians, and we carry parts for Carrier, Trane, Lennox, and other major brands to avoid delays. Call (855) 467-1888 for a free estimate.
We’ve been driving to San Francisco from our Sacramento base for 16 years, and we’ve learned that heating problems here aren’t like heating problems anywhere else. The city didn’t grow up with central forced-air systems. It grew up with wall furnaces wedged into narrow 25-foot lots, balloon-frame walls with no insulation, and zero ductwork. When a heating system fails in a San Francisco flat, it’s rarely a simple swap. It’s a retrofit puzzle. That’s why owner Jason Trent stays active as Field Supervisor on these jobs, not just dispatching techs from an office.
Why Stonegate Heating & Air California Is San Francisco’s Preferred Heating & Furnace Company
Our reputation in San Francisco is built on jobs other companies walk away from. We’ve got 499 verified reviews averaging 4.7 stars, and a significant share of those come from San Francisco homeowners who called us after another contractor said their building was “too old” or their brand “too obscure.” We don’t use that language. Our Heating & Furnace team is factory-trained or experienced on nine brands: Carrier, Trane, Lennox, Goodman, Rheem, York, Daikin, Bryant, and American Standard. Whatever unit you have, we’ve probably worked on it.
Response time to San Francisco matters, especially during the cold snaps that hit the eastern neighborhoods hardest. The Mission, SoMa, and the Tenderloin sit in a thermal belt that runs 10–15°F hotter than the western fog belt in summer, but the same exposure means faster temperature drops when winter storms push through. We schedule San Francisco calls with realistic arrival windows and keep you updated if traffic on the Bay Bridge or 101 shifts our timing.
Jason Trent supervises every project personally. That’s not a marketing line. It’s how we operate. In a city where a heating job can involve negotiating access with three TIC co-owners and fishing electrical through lath-and-plaster shared walls, having the owner on-site prevents the miscommunications that turn a one-day job into a week-long ordeal. San Francisco’s building stock demands that level of accountability.
Our Heating & Furnace Services in San Francisco
Furnace Repair
Most furnace repair calls we get in San Francisco aren’t about central furnaces at all. They’re about wall furnaces, original gas units from Wedgewood, Empire, or similar manufacturers that have heated Tenderloin and Mission flats for 60-plus years. The failure pattern is predictable: the thermocouple dies, the pilot assembly is discontinued, and the homeowner faces a choice between a custom parts hunt and replacement. A typical furnace repair in San Francisco runs $175–$825, depending on whether we’re sourcing a rare thermocouple or rebuilding the gas valve. In a Victorian flat on Jessie Street in SoMa, we found the original Empire wall furnace had a failed thermocouple and the pilot assembly was no longer available. We recommended installing a ductless mini-split with heat pump instead, which involved running a new 240V line through plaster walls and mounting the indoor head on a shared wall, a job common in these narrow 25-foot lots.
Furnace Replacement
Replacing a furnace in San Francisco is almost always a retrofit. The original building has no ductwork. The walls are plaster-over-lath. The electrical panel may be original knob-and-tube or early Romex that can’t handle a modern furnace’s load. We price furnace replacement after a site visit, because every job is custom. The ZIP codes we cover, 94117 through 94120, are dense with multi-unit TICs and flats where routing refrigerant lines and electrical through shared walls requires sign-off across multiple owners. We handle that coordination. For many San Francisco properties, we recommend ductless mini-split heat pumps rather than forcing a central system into a building never designed for one. The equipment is more efficient, the installation is less destructive to original plaster, and you get cooling for the increasingly severe Bay Area heat events that old San Francisco buildings were never built to handle.
Furnace Tune-Up
A furnace tune-up in San Francisco costs $95–$235 and should happen every fall before the heating season starts. For wall furnace owners, this is critical. These units burn in tight spaces with limited combustion air, and the pilot orifices clog faster than in suburban installations with dedicated utility rooms. We clean burners, test gas pressure, check thermocouple output, and inspect heat exchangers for cracks that could vent carbon monoxide into living spaces. In balloon-frame buildings, cold air infiltration through uninsulated stud cavities already makes old furnaces cycle excessively and drive up gas bills. A poorly tuned unit just makes it worse. We document everything and flag parts that are approaching end-of-life, so you’re not surprised by a mid-winter failure.
Heat Exchanger Inspection & Replacement
Cracked heat exchangers are a safety issue we take seriously. In San Francisco’s older housing stock, we’ve found heat exchanger failures in wall furnaces that have been running continuously for decades, their metal fatigued from thousands of on-off cycles. We use combustion analyzers and visual inspection tools to check for CO leakage. If the heat exchanger is cracked, we don’t patch it. We replace it or recommend unit replacement, depending on parts availability and the overall condition of the furnace. This is not a corner to cut. Carbon monoxide in a small San Francisco flat with limited ventilation is a genuine hazard.
What happens when you call
- 1
A real person answersNo phone trees — you reach a local pro.
- 2
You get an upfront price rangeHonest numbers before anyone is dispatched.
- 3
A background-checked tech heads outLicensed & insured, dispatched right away.
- 4
You approve before work beginsNothing starts until you say go.
Trusted Brands We Service in San Francisco
We work on Carrier, Trane, Lennox, and every other major brand, but in San Francisco we probably spend more time on discontinued wall furnace brands than on any current product line. That’s the reality of the market. We maintain relationships with regional parts distributors and salvage yards to source thermocouples, gas valves, and pilot assemblies for units that haven’t been manufactured in 30 years. When a part truly can’t be found, we pivot to replacement with modern equipment sized correctly for your space and your building’s electrical capacity. Fast turnaround matters in San Francisco, where a night without heat in an uninsulated Edwardian flat is genuinely uncomfortable. We stock common components for American Standard and Bryant systems as well, so if you do have a newer installation, we’re not ordering parts from out of state.
Common Heating & Furnace Problems We See in San Francisco Homes
- Discontinued pilot assemblies on original wall furnaces. Wedgewood and Empire units from the 1950s–1970s are everywhere in the Tenderloin and Mission, and their pilot assemblies haven’t been made in decades. We source from salvage or recommend replacement when the hunt isn’t worth the cost.
- Cold air infiltration through balloon-frame cavities. San Francisco’s pre-1920 buildings have no insulation in the stud bays. Wind off the Pacific pushes straight through, making furnaces cycle constantly and gas bills spike. We identify this during service calls and recommend weatherization alongside heating repairs.
- Zero low-voltage wiring when adding new equipment. Many San Francisco flats were built with no thermostat wiring at all. Installing a modern furnace or mini-split means fishing new low-voltage lines, or often a full 240V circuit, through original lath-and-plaster. It’s labor-intensive but routine for us.
- Oversized or undersized equipment from bad load calculations. The thermal belt effect in eastern San Francisco neighborhoods means standard sizing charts don’t work. A system adequate for the Richmond or Sunset will struggle in the Mission or SoMa. We calculate loads neighborhood by neighborhood.
Pricing for Heating & Furnace in San Francisco, CA
San Francisco’s housing stock makes heating work more labor-intensive than in cities with standard suburban construction. Fishing electrical through plaster, coordinating with TIC co-owners, and sourcing discontinued parts all add time. Here’s what we typically see:
| Service | Typical Range in San Francisco |
|---|---|
| Furnace Repair | $175–$825 |
| Furnace Tune-Up | $95–$235 |
Replacement pricing varies widely based on equipment choice and installation complexity. A straightforward wall furnace swap in a single-unit flat is at the lower end. A multi-head ductless mini-split retrofit in a three-story TIC with plaster walls and no existing electrical is a different project entirely. We provide itemized, upfront quotes after a free site visit. No vague estimates, no mid-project surprises. Call (855) 467-1888 to schedule.
We Also Serve Cities Near San Francisco
Our service area extends throughout San Francisco and into surrounding neighborhoods. We regularly work in the Mission District, Noe Valley, Chinatown, and Visitacion Valley, handling the same legacy heating challenges, from original wall furnaces in Victorian flats to modern system installations in updated condos. The building stock changes block by block, and we adjust our approach accordingly.
Serving San Francisco, CA — Our Local Coverage Area
We’re based in the San Francisco area and know this community well. Use the map below to see our service coverage — if you’re nearby, we can almost certainly help.
FAQs — Heating & Furnace in San Francisco
The most common cause is a failing thermocouple, a safety device that shuts off gas flow if the pilot flame is weak or absent. In Mission District flats with original Wedgewood or Empire wall furnaces, thermocouples fatigue after decades of use, and drafty balloon-frame walls can blow the pilot out entirely. We test thermocouple output with a millivolt meter and check for combustion air issues. If the part is discontinued, we’ll explain your repair-versus-replacement options clearly. Call (855) 467-1888 for a free diagnostic.
Yes, and we often recommend it. Ductless mini-splits with heat pump capability provide both heating and cooling without ductwork, which makes them ideal for San Francisco’s pre-1920 buildings. The challenge is electrical: many Tenderloin flats have no 240V circuit at the exterior wall and no low-voltage thermostat wiring. We handle the full electrical retrofit, including fishing lines through lath-and-plaster and coordinating with your building’s electrical service capacity. The installation is more involved than a standard swap, but the result is efficient, quiet, and adds cooling for Bay Area heat events. Call (855) 467-1888 for a site assessment.
Yes, a failed ignitor is a likely cause if your gas furnace starts but never reaches temperature. In 1920s San Francisco buildings, we’ve also found that blocked burners from years of dust accumulation, or cracked heat exchangers that trigger safety shutoffs, produce the same symptom. We don’t guess. We test the ignitor’s resistance, inspect the flame sensor, and check for CO leaks before declaring a repair. Safety first, especially in older buildings with limited ventilation. Call (855) 467-1888 and we’ll diagnose it properly.
Wedgewood and Empire dominate the surviving original installations in San Francisco Edwardians and Victorians, with some Williams and Cozy units mixed in. These were manufactured from the 1930s through the 1970s and were designed for the small, closed rooms typical of the era. Parts availability is the deciding factor in whether we can repair or must replace. We maintain a running inventory of salvaged components, but when the supply dries up, we recommend modern replacements sized for your actual heat load, not the original unit’s outdated rating. Call (855) 467-1888 to discuss what’s possible for your specific unit.
Most gas furnace replacements in SoMa condos and flats fall in a range that depends heavily on whether you’re keeping a wall furnace format or upgrading to a ductless system. A direct wall furnace replacement with a modern equivalent starts lower, while a multi-zone ductless mini-split retrofit with full electrical work runs higher. The narrow 25-foot lots and shared walls in SoMa add coordination complexity, especially in TIC buildings. We provide exact quotes after a free site visit where we assess your electrical, your building’s constraints, and your heating and cooling goals. Call (855) 467-1888 to schedule yours.
Ready to get your San Francisco home’s heating system sorted? Whether you’ve got a failing wall furnace in the Mission, a 1920s boiler in Noe Valley, or you’re finally adding cooling to a Tenderloin flat, we’ll give you a straight answer and a fair price. Owner Jason Trent supervises every project. We’ve got 16 years and nearly 500 reviews to back up our work. Call (855) 467-1888 for a free estimate.
Written by Jason Trent, Owner at Stonegate Heating & Air California, serving San Francisco since 2008.