The short answer
SwiftAir repairs furnaces, heat pumps and wall heaters in Fremont homes, starting with a full diagnosis so you know what failed and why before any work begins. Bay Area Air District rules do not force you to replace a working furnace, so repair is often a sensible choice when the system is otherwise sound.
When the heat stops working in a Fremont home, it is usually on a chilly, damp morning, often the first time the system has run in months. SwiftAir Conditioning Repair diagnoses and fixes gas furnaces, heat pumps, and wall and floor heaters for homes across Fremont, including the 94536, 94538, 94539 and 94555 ZIP codes. We are based in San Jose, about 8 miles south, so Fremont is a short drive for us. This page covers the heating problems we see most, what a repair visit looks like, and how to weigh repair against replacement under current Bay Area rules.
Heating problems we see in Fremont homes
Fremont winters are mild compared with much of the country, so many heating systems sit idle for long stretches. Idle equipment tends to show its problems all at once. Dust settles on burners and sensors, filters clog without anyone noticing, and small electrical faults surface the first time the system is asked to run for hours.
These are the issues that most often lead to a call:
- Furnace blows cold air or shuts off after a few minutes, often a dirty flame sensor or an overheating safety limit
- Igniter clicks or glows but the burners never light
- Heat pump runs constantly in heating mode but the house stays cool
- Burning-dust smell that lasts longer than the first few minutes of the season
- Loud bangs, squeals or rattling from the blower or burners
- Thermostat calls for heat but nothing happens
- Older wall or floor furnaces that will not stay lit
What happens on a heating repair visit
We start by asking what you have noticed: when the problem started, any sounds or smells, and whether the system worked at all this season. Then the technician checks the thermostat, power and gas supply, and the filter before moving on to the equipment itself.
On a gas furnace, that means inspecting the igniter, flame sensor, burners, pressure switch, inducer motor, blower and safety limits, and reading any error codes from the control board. On a heat pump, we check refrigerant pressures, the reversing valve, the defrost cycle, the outdoor fan and the backup heat strips if your system has them.
Once we find the cause, we explain it in plain terms, tell you what the repair involves, and get your approval before doing the work. If we find something unsafe, such as a cracked heat exchanger or a gas leak, we will tell you directly and shut the equipment down rather than leave it running.
Repair or replace: Bay Area rules to know
Fremont is in Alameda County, which falls under the Bay Area Air District. Under the District's Rule 9-4, natural gas furnaces manufactured from 2029 onward must meet a zero-NOx emission standard. In practice, that points homeowners toward heat pumps when a furnace is replaced after that date.
The rule does not require you to replace working equipment. It applies only when an existing furnace fails or is replaced. If your furnace is in good shape apart from a failed part, repairing it is a reasonable choice, and we will say so. If the system is older and needing repeated major repairs, we will walk you through what a heat pump would mean for your home so you can plan on your own schedule instead of during an emergency.
Water heaters fall under a separate rule, Rule 9-6, with a zero-NOx date for small units set for 2027. The Air District Board is considering amendments in November 2026 that could delay it, so check the current rule before planning a water heater replacement.
Incentives and tax credits
The federal Energy Efficient Home Improvement Credit covered qualifying heat pumps placed in service before December 31, 2025. It is not available for new installations after that date, so do not count on it if you are switching to a heat pump now.
Bay Area homeowners can check BayREN and their local clean energy provider for current heat pump and electrification incentives. Amounts and availability change by funding cycle, so we confirm the current offer before including it in any quote.
Quick checks before you call
A few simple checks can save you a visit, or help us diagnose faster when we arrive:
- Make sure the thermostat is set to Heat and a few degrees above room temperature, and replace its batteries if it has them
- Check the breaker for the furnace or heat pump and the service switch near the unit
- Replace a dirty filter
- On a gas furnace, confirm other gas appliances in the home are working
- If you smell gas, leave the house and call your gas utility or 911 from outside before calling us
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