The short answer
MasterFix repairs furnaces and heat pumps in Los Altos homes, starting with a diagnosis of the real cause before any parts are replaced. Bay Area rules don't force you to replace working equipment, so repair is often a reasonable choice. We offer 24/7 emergency service for no-heat and safety problems.
When your furnace or heat pump quits on a cold, damp Los Altos evening, you want a clear answer about what's wrong and what it will take to fix it. MasterFix HVAC Repair Service travels about 12 miles northwest from our San Jose base to repair heating systems in homes across Los Altos (ZIP 94024). We diagnose the actual cause, explain your options in plain terms, and get the heat back on. For urgent problems, we offer 24/7 emergency service.
Heating Problems We See in Los Altos Homes
The Santa Clara Valley has mild, damp winters, so many Los Altos heating systems sit idle for months and then run in short bursts when the weather turns. That pattern causes its own set of problems. Dust settles on burners and sensors over the summer. Igniters and flame sensors that worked fine last spring can fail on the first cold night. Thermostats with weak batteries or loose wiring may stop calling for heat at all.
Heat pumps have different weak points. On chilly, wet mornings, the outdoor unit has to defrost itself, and a faulty defrost control or sensor can leave you with lukewarm air or an outdoor coil covered in frost. The most common issues we repair include:
- Furnace won't ignite, or lights and then shuts off after a few seconds
- Blower runs but the air coming out is cool
- Short cycling, where the system turns on and off too often
- Banging, squealing, or rattling from the furnace or air handler
- Heat pump stuck in defrost or not switching into heating mode
- Uneven heat between rooms or floors
- Thermostat not responding or reading the wrong temperature
What Happens During a Heating Repair Visit
We start by asking what you've noticed: when the problem began, any sounds or smells, and whether it happens all the time or only sometimes. Then we inspect the system step by step. That includes the thermostat, filter, ignition and flame sensing, gas valve, blower motor, limit switches, and venting on a furnace. On a heat pump, we also check refrigerant-side performance and the defrost controls.
Once we find the cause, we explain it and tell you what the repair involves before we start. If a part is worn but still working, we'll point it out so you can plan ahead. We don't swap parts on a guess. Replacing the wrong component costs you time and money and leaves the real problem in place.
Repair or Replace? What Local Rules Mean for You
Many Los Altos homeowners have heard that gas furnaces are being phased out. The details matter. Under the Bay Area Air District's Rule 9-4, natural gas furnaces manufactured starting in 2029 must meet a zero-NOx emission standard. In practice, that points homeowners toward heat pumps when they replace a furnace after that date.
The Air District rules do not require you to replace equipment that works. They only apply when an existing furnace fails or is replaced. If your furnace can be repaired safely and reliably, keeping it running is a legitimate choice. We'll give you an honest read on its condition so you can decide when a change makes sense for your home.
If you're weighing a heat pump, know that the federal Energy Efficient Home Improvement Credit (25C) only covered qualifying heat pumps placed in service before December 31, 2025. It isn't available for new installations. Local programs through BayREN and your clean energy provider may offer heat pump incentives. Amounts and availability change by funding cycle, so we confirm the current offer before including it in any quote.
When to Call Right Away
Some heating problems shouldn't wait until morning. If you smell gas, leave the house and call your gas utility or 911 from outside before calling us. If your carbon monoxide alarm goes off, get everyone out and get emergency help. Once the immediate danger is handled, we can find and fix the source. Our 24/7 emergency service also covers no-heat situations when someone in the home is elderly, very young, or has health concerns, and furnaces that trip a breaker or give off a burning smell.
Serving Los Altos and Nearby Communities
Along with Los Altos, our technicians repair heating systems throughout this part of Santa Clara County, including Los Altos Hills, Mountain View, Sunnyvale, Cupertino, and Santa Clara. Whether your home has an older gas furnace, a newer heat pump, or a system you aren't sure about, we can diagnose it and walk you through your options.
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