From the hallway, a furnace that will not heat looks the same no matter what broke. Inside the cabinet, though, everything happens in a strict order: inducer on, pressure switch closed, igniter glowing, gas valve open, burners lit, flame proven, and finally the blower moving heat through the ducts. Diagnosis is mostly a matter of finding where that chain breaks. In Mountain View homes, it tends to be the same handful of culprits: a flame sensor coated in oxide, a hot surface igniter cracked by thermal cycling, a pressure switch held open by a tired inducer or a plugged condensate trap, or a control board with a burned relay.
Rather than guess, Mountain View HVAC tests the sequence one stage at a time. We read igniter resistance, measure flame signal in microamps, check that the pressure switch responds to real inducer draft, confirm voltage at the gas valve, and test the blower and its capacitor. Because this is a fuel-burning appliance, the safety basics come with every visit: we inspect the heat exchanger, leak-test the gas connections, and verify flue draft. You cannot tell a furnace problem from a furnace hazard by looking at the thermostat. Before we leave, temperature rise is measured against the data plate so airflow and flame are matched as the manufacturer intended.
We work on natural gas, propane, and electric furnaces from every major brand, both conventional 80 percent units and condensing high-efficiency models with their traps, drains, and dual pressure switches. The truck stock covers the parts that actually fail: igniters, flame sensors, pressure switches, capacitors, inducer assemblies, and blower motors, so most repairs finish in one trip. For furnace repair anywhere in Mountain View, call (650) 220-0820 and we will get the burners lit today.
When the AC quits in summer, see AC Repair in Mountain View.
How Much Does Furnace Repair Cost in Mountain View?
For most Mountain View homes, a furnace repair runs $150 to $600. Ignition and sensor problems are usually the least expensive, while blower motors, control boards, and heat exchangers cost more. Mountain View HVAC tests the system, finds the actual fault, and quotes the repair before any work begins.
| Repair | Typical cost | What it usually means |
|---|---|---|
| Flame sensor cleaning or replacementFurnace lights, then shuts off within seconds | $80–$250 | Burners light but cut out almost immediately |
| Hot surface igniter replacementFurnace clicks and tries to start but never lights | $150–$400 | Furnace clicks and tries to start but never lights |
| Draft inducer motorStartup fan fails, furnace won't fire | $400–$1,000 | Startup fan fails, furnace won't fire |
| Blower motorBurners run but little or no air comes out of the vents | $400–$1,500 | No airflow, or the blower runs nonstop |
| Control boardErratic behavior, error codes, or no response at all | $300–$700 | Furnace won't respond to the thermostat |
| Gas valve replacementIgniter glows but gas never flows to the burners | $250–$700 | Igniter glows but gas never flows to the burners |
Ranges are typical for these repairs; you get an exact quote before any work starts.
What Moves the Cost Up or Down
- The age and efficiency of the furnace, since high-efficiency models use more specialized parts
- A cracked heat exchanger, which is a safety issue and usually points to replacement
- Timing, such as a no-heat call on a cold night versus a scheduled repair
- Access to the furnace in attics, closets, or crawlspaces
If your furnace is past 15 to 20 years old or the repair is a major one, we'll give you repair and replacement prices side by side. No heat right now? Call (650) 220-0820.
Signs You Need Furnace Repair in Mountain View
Catching these issues early helps you avoid costly problems and protect your property. Keep an eye out for the following clues that it's time to bring in an expert:
- Squealing or grinding from the blower compartment
- The furnace clicks and glows but the burners never light
- Booming or banging at light-off from delayed ignition
- A furnace that shuts off every few minutes before the house warms up
- Yellow, wavering burner flames where they should be sharp blue
- Air moving through the vents that never gets warm
- Burners light, run a few seconds, then shut down repeatedly
- Rust streaks, soot, or water around the cabinet or flue
Act Before It Gets Worse
Most HVAC failures start small, a weak capacitor, a squealing blower, a system that runs a little longer each week. If you notice any of these signs, contact Mountain View HVAC at (650) 220-0820 for a prompt inspection.
Your Furnace Repair Questions Answered
Why Professional Furnace Repair Matters
A furnace combines gas, flame, high voltage, and a flue in one cabinet, and the failure that matters most is the one you cannot see from outside: a compromised heat exchanger passing combustion gases into the air your blower pushes through the house. Delayed ignition that booms at light-off stresses that exchanger further every morning it goes unfixed. Meanwhile the diagnostic traps stack up: a furnace that trips its high limit may have a bad switch, or it may be protecting itself from a clogged filter or a dying blower, and replacing the switch in the second case just removes a safety while leaving the fault.
Our experienced technicians look at every symptom in the context of the whole furnace. We measure flame signal instead of assuming it, which keeps us from replacing a healthy sensor while a cracked igniter or weak gas valve slips past. Draft is confirmed at the pressure switch and at the flue. Temperature rise is checked against the data plate, catching airflow problems before they shorten the life of the heat exchanger. The gas side is leak-tested with instruments, never with a quick sniff. The result is a furnace proven safe over a full cycle, plus an honest opinion if the unit is getting close to the point where replacing it beats repairing it again.
Our Furnace Repair Process
Our systematic workflow delivers thorough, lasting results on every job. Here's what you can expect when you choose Mountain View HVAC:
Startup Sequence Testing
The furnace is run through its startup while we measure inducer draft, pressure switch response, igniter resistance, flame signal, and gas valve operation. The goal is to pinpoint the exact step that fails.
Safety Verification
On every visit, we inspect the heat exchanger, leak-test the gas connections, and confirm the flue is drafting. A repair is not complete until the unit is proven safe.
Expert Repair
Igniters, flame sensors, pressure switches, capacitors, and motors ride on the truck, so most furnaces are lit and heating again before we pack up.
Complete Verification
We finish with a full-cycle test: temperature rise matched to the data plate, smooth ignition with no booming, and every limit switch and safety control confirmed working.
Furnace Repair Prevention Tips
A few simple habits now, like regular filter changes and seasonal tune-ups, can add years to your system's life. Here are our expert recommendations:
- If you have a high-efficiency furnace, check that the condensate drain is flowing freely
- Notice how the furnace sounds at startup, because a quiet light-off is healthy and a boom is not
- Give the furnace room to breathe, since a crowded utility space starves the burners of air
- Put in a fresh filter monthly through the heating season, the cheapest protection your furnace can get
- Keep storage, lint, and especially chlorine-based products away from the furnace closet
- Put a carbon monoxide detector on every level and test them monthly
- Schedule service each fall to catch worn igniters and dirty sensors before cold weather arrives
Should You DIY or Call a Pro?
A homeowner can swap a filter with ease, but diagnosing capacitors, refrigerant charge, control boards, and error codes calls for the equipment and know-how only a pro brings. Consider the following comparison:
| Factor | DIY Attempt | Professional Service |
|---|---|---|
| Exchanger Cracks | Cracks invisible from the outside | Checked every time we open the unit |
| Ignition Faults | Guesswork based on blink codes | Each ignition component tested |
| Gas Connections | Connections judged by smell | Instrument leak test on each visit |
| High-Limit Trips | Limit replaced, cause left behind | Root cause of overheating corrected |
| Blower Setup | Fan speed never checked | Temperature rise set to the data plate |
| Final Check | Declared fixed after one flame | Clean, safe operation verified over full cycles |
Schedule Your Furnace Repair Service
Every day you wait puts more strain on a struggling unit. Get Mountain View HVAC on the job today.
Get Help: (650) 220-0820Furnace Repair Across the Mountain View Area
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