Seasonal tune-up and full diagnostic on your Carrier, Trane, or Goodman system - readings shown to you before any repair is proposed
Diagnosis first, numbers second - you approve the repair price before a single part goes in.
Fast, Reliable Furnace Repair Across Los Altos
Most furnace repairs in Los Altos run $150-$700 and are completed in a single visit, with our technicians carrying parts for Trane, Lennox, Carrier, and other major brands on every truck. We dispatch from our San Francisco Bay Area office and typically arrive in Los Altos within the same day, including calls from the Loyola Corners, North Los Altos, and Rancho neighborhoods. If your furnace quit on a cold January morning or your blower won’t stop cycling, call (817) 402-2972 - a live person answers, 24 hours a day, and we’ll give you a firm arrival window we actually keep.
Los Altos homeowners deal with a heating problem most of Santa Clara County doesn’t talk about: marine air funnels through the Santa Cruz Mountains gaps right into this city, so outdoor furnace and condenser cabinets here corrode years ahead of inland equipment. Coastal salt fog accelerates rust on burner assemblies and gas valves in furnace compartments, demanding an annual inspection interval that San Jose contractors don’t need to recommend. We’ve been handling this exact issue since 2003, and our Furnace Repair team knows which coated components and corrosion-resistant options are worth the premium in this specific microclimate.
Why Coldharbour Heating & Air Is Los Altos’s Preferred Furnace Repair Company
We’re independently owned and operated under the Kingswell network, which means we follow The Kingswell Way: say the price before the work starts, show up in the window given, leave the place cleaner than found, put the guarantee in writing, and come back if it fails. Los Altos homeowners have told us this matters more here than elsewhere - too many neighbors have paid Silicon Valley prices for Peninsula-level service that never showed or changed the bill at the door.
Our technicians are background-checked, uniformed, and trained on nine major residential HVAC brands including Carrier, Trane, Lennox, Goodman, Rheem, York, Daikin, Bryant, and American Standard. When you call (817) 402-2972, you reach a live person, not a voicemail tree, any hour of any day. We serve Los Altos with the understanding that a failed furnace in January isn’t just uncomfortable - it’s a genuine health risk for older residents and young children, especially in the draftier original ranch homes that dominate this city’s housing stock.
Every repair comes with our 365-Day Done Right Promise in writing: if the fix fails within a full year, we return and correct it at no charge. No argument, no additional fee, no expiration games. The guarantee goes on paper before the technician leaves your driveway.
Heating Repair in Los Altos
Heating Repair in Los Altos means diagnosing why your furnace, heat pump, or auxiliary heating system isn’t delivering warm air - and fixing it without the runaround. Given this city’s 1950s-1970s ranch housing stock, we regularly find systems that were engineered for heating only, with ductwork routed through unconditioned attics that hit 140°F in summer and drop below 40°F in winter. That thermal cycling cracks heat exchangers and warps blower housings over decades. Most Heating Repair calls in Los Altos fall between $150-$700, with simpler fixes like ignitor replacements or flame sensor cleanings at the lower end and heat exchanger work or gas valve replacement toward the higher end.
Heat Exchanger and Combustion Safety
A cracked heat exchanger is the repair we never let slide - it can leak carbon monoxide into your home. In Los Altos, we find these cracks accelerated by marine humidity attacking metal that’s already been thermal-cycling for 40-60 years. We test with combustion analyzers, show you the readings, and explain exactly what we’re seeing before we quote any replacement.
Ignition and Flame Control Issues
Older furnaces in Los Altos use either a standing pilot or hot surface ignitor; newer systems use intermittent spark. Salt fog corrodes ignition modules and flame sensors, especially on slab foundations and shallow crawls where moisture gets trapped. We clean what we can, replace what we must, and always verify flame signal strength before we leave.
Boiler Repair in Los Altos
Boiler Repair in Los Altos is less common than furnace work - most local homes use forced-air gas furnaces - but the hillside properties near Portola Valley Road and the custom builds in North Los Altos sometimes run hydronic systems. When a boiler fails here, it’s usually a circulation pump, a failed aquastat (the temperature control that tells the burner when to fire), or sediment buildup from decades of heating the same water through original copper loops. Most Boiler Repair calls in Los Altos run $150-$700, similar to furnace work, though parts for older European brands can take longer to source.
Hydronic Zone Control Problems
Multi-zone boiler systems in larger Los Altos homes often suffer from stuck zone valves or failed actuators. One room overheats while another stays cold. We diagnose whether it’s the valve, the thermostat, or the control board, and we quote the repair before we open a single tool.
Boiler Pressure and Expansion Tank Failures
Los Altos’s water chemistry varies by neighborhood, and hard water scale can plug boiler heat exchangers or cause pressure spikes that trip safety relief valves. We check expansion tank pre-charge, test pressure relief operation, and flush what we can without disassembling the system.
Trusted Brands We Service in Los Altos
Our trucks carry common repair parts for Trane, Lennox, Goodman, and Rheem - the four brands we see most often in Los Altos’s original ranch homes and recent luxury rebuilds. We also service Carrier, Bryant, American Standard, York, and Daikin. Because we dispatch from the Bay Area, we can source same-day or next-morning parts for less common failures, and our technicians are trained to factory standards on each manufacturer’s ignition sequence, safety lockout logic, and warranty requirements. If your furnace is under manufacturer warranty, we’ll document the repair correctly so you don’t lose coverage.
Common Furnace Repair Problems We See in Los Altos Homes
- Coastal salt fog corrosion on burners and gas valves. Marine-layer moisture accelerates rust in outdoor furnace compartments and rooftop units, causing intermittent ignition or complete flame failure years before inland systems show the same wear. We inspect these components annually in Los Altos, not biennially.
- Heat exchanger cracks from attic thermal cycling. Original 1950s-70s ranch ducts run through unconditioned attics where summer heat and winter cold stress metal. We’ve replaced heat exchangers in Loyola Corners homes where the furnace was only 12 years old because attic conditions aged it prematurely.
- Slab moisture rusting ignition modules and flame sensors. Los Altos’s slab foundations and shallow crawls trap humidity, especially near the groundwater table in lower-elevation neighborhoods. Carrier, Trane, and Lennox furnaces from the 1990s and 2000s are particularly susceptible.
- High-limit switch trips from restricted airflow. Original ductwork in Los Altos was sized for heating-only static pressure. When homeowners add filtration or close too many vents, furnaces overheat and shut down on safety. We measure static pressure and tell you whether the fix is a filter change or duct modification.
Pricing for Furnace Repair in Los Altos, CA
We give you a written price before any work begins, and that price does not change when we’re done. Here’s what furnace repair typically costs in the Los Altos market:
| Service | Price Range |
|---|---|
| Furnace Repair (diagnostic + repair) | $150-$700 |
| Annual Furnace Tune-Up | $80-$200 |
Where your repair falls in that range depends on the part failed, whether we have it on the truck, and how accessible your furnace is. An ignitor replacement on a 2015 Goodman in a garage closet is straightforward. A heat exchanger replacement on a 1987 Carrier in a Rancho crawlspace is not. We diagnose for a flat fee, hand you the written price, and you decide before we proceed. Estimates are free, and there’s no charge if you choose not to repair. Call (817) 402-2972 for an exact quote on your system.
We Also Serve Cities Near Los Altos
Our technicians regularly cross between Los Altos and neighboring communities - Mountain View to the east, Stanford and Palo Alto to the north, and Portola Valley to the west. The same marine-influenced climate patterns affect furnace equipment across this corridor, and we apply the same corrosion-prevention protocols and annual inspection standards throughout. If you’re in one of these nearby cities and need furnace repair, the same live-answer phone line and written guarantee apply.
Serving Los Altos, CA - Our Local Coverage Area
We’re based in the Los Altos 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 About Furnace Repair in Los Altos
Annually, without exception - the salt fog here accelerates corrosion on burners, gas valves, and ignition components faster than inland Santa Clara Valley climates demand. We recommend every fall, before the first cold snap, and we check coated-cabinet condition on outdoor units as part of every tune-up. Call (817) 402-2972 to schedule; tune-ups run $80-$200.
Usually, with modifications. Original 1950s-70s ranch ducts were sized for heating-only static pressure and often leak 20-30% of conditioned air into unconditioned attics. We measure airflow and static pressure before recommending any furnace replacement, and we’ll tell you honestly whether your ducts need sealing, partial replacement, or just a filter upgrade. On a 1962 ranch in the Loyola Corners area, our tech found the furnace’s heat exchanger cracked and the blower motor seized - a direct result of 60 years of marine-layer humidity warping the original metal. We installed a Carrier 80% AFUE furnace, sealed the static pressure leaks in the 1950s-era ductwork, and added a coated outdoor cabinet to resist the salt fog that had already rusted the old unit’s base pan.
Marine air funnels through the Santa Cruz Mountains gaps directly into Los Altos, carrying salt fog that corrodes outdoor furnace compartments and rooftop units years ahead of inland equipment. San Jose’s east side sits in a rain shadow with drier, hotter summers and less salt exposure. The difference is real, measurable, and why we recommend coated components and annual inspections here that San Jose contractors don’t need to push.
We repair all major residential brands including Trane, Lennox, Goodman, Rheem, Carrier, Bryant, American Standard, York, and Daikin. Our trucks stock the most common failure parts for the brands we see most in Los Altos - Trane, Lennox, Goodman, and Rheem - which means faster same-day completion for most repairs. Call (817) 402-2972 with your model number and we’ll confirm parts availability.
Title 24 requires specific efficiency and airflow standards for any heating system modification, and Los Altos falls under Bay Area Air Quality Management District rules that increasingly favor electrification and low-NOx equipment. A straightforward repair - replacing a failed gas valve or ignitor - doesn’t trigger full compliance review. But if your furnace is beyond repair and you’re replacing it, we handle the Title 24 documentation, permit coordination, and rebate paperwork as part of the installation quote. For repair work, we focus on fixing what’s broken correctly and safely, and we flag any compliance issues we spot.
Ready to get your furnace fixed right? Call Coldharbour Heating & Air at (817) 402-2972 for a free estimate. A live person answers 24/7, we’ll give you a firm arrival window, and every repair comes with our 365-Day Done Right Promise in writing.
Written by Victor Mancini, Owner at Coldharbour Heating & Air, serving Los Altos since 2003.







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