Furnace Not Heating in Richmond, CA | Bay Area HVAC Service

Furnace Not Heating in Richmond

Heating is the HVAC system that matters most in Richmond. Summers stay in the 60s and low 70s off the bay, and a lot of homes here never had AC at all. The furnace is what carries the house. So when it stops producing heat on a foggy 45-degree morning, it shows up as a problem the same day rather than something you ignore for a week.

The good news is that a furnace that fans but blows cold, or won't light at all, is almost never a dead unit. The igniter, flame sensor, gas valve, or a tripped limit switch from a clogged filter accounts for most no-heat calls. These are repairs, not replacements. We diagnose the actual failed component before we quote anything.

Richmond's older post-war housing complicates one thing: many of these furnaces are 18-plus years old, and at that age we also have to rule out a cracked heat exchanger before we hand the system back to you. That is a safety check, not an upsell. We test CO and inspect the exchanger on every gas furnace call here.

Common causes

Cracked or worn-out hot surface igniter. This is the single most common no-heat call on modern furnaces. The igniter glows to light the burners, and the ceramic element cracks with age and thermal cycling. We test it for continuity and resistance, confirm it isn't glowing, and replace it with the correct part for your model. The replacement runs roughly $200 to $350 and the system is back in minutes.

Dirty flame sensor. The flame sensor proves the burner actually lit. When carbon builds up on it, the furnace fires for a few seconds then shuts down, sometimes cycling over and over. Cleaning the sensor fixes most cases. If the rod is degraded we replace it, usually $150 to $200. We check this early because it is cheap and common.

Clogged filter tripping the limit switch. A filter nobody changed for a year chokes airflow, the heat exchanger overheats, and the high-limit switch shuts the burners off to protect the system. The furnace blows cold or short-cycles. We pull the filter, confirm airflow, and reset the limit. If the limit switch itself is fatigued we replace it. Often this is a same-visit fix with a filter and a cleaning.

Failed gas valve or no gas to the burners. If the igniter glows but the burners never light, the gas valve may not be opening. We check the valve coil, verify gas pressure, and rule out a closed manual valve or a tripped safety upstream. A failed valve gets replaced; a closed supply gets corrected and documented.

Cracked heat exchanger on an older furnace. On Richmond's older 18-plus-year furnaces, a cracked heat exchanger is a real possibility and a CO safety issue. We inspect with a camera and show you the crack before we say a word about cost. A confirmed crack usually means the furnace is at end of life, and on a unit this old, heat pump conversion is frequently the better path given Richmond's mild winters.

Thermostat or control board fault. Sometimes the furnace is fine and the thermostat lost its program, its batteries, or its connection. Other times the control board has a failed relay and won't sequence ignition. We meter the board and the thermostat wiring before condemning either, because a $30 thermostat issue should never get billed as a board.

How we diagnose it

Thermostat call for heat, batteries, and wiring at the board to confirm the furnace is actually getting the signal
Igniter continuity and glow, then flame sensor microamp signal during a firing cycle
Filter condition and airflow, plus the high-limit switch for a trip caused by restriction
Gas valve operation and supply pressure if the igniter glows but burners don't light
CO levels and heat exchanger integrity by camera on every gas furnace, especially older units

$75 diagnostic, credited toward any repair over $200. You get a written quote before any work begins.

Furnace Not Heating in Richmond: common questions

Do you actually cover Richmond, or are you mostly a Tri-Valley company?

We're based in San Ramon and we cover the inner East Bay including Richmond, Berkeley, and Oakland regularly. Richmond is a bit further from the shop than our home cities, so we'll give you an honest arrival window when you call rather than a vague same-day promise. Heat-out calls get prioritized.

My furnace is old and Richmond barely gets cold. Is it worth replacing or should I just keep repairing?

That's exactly the conversation Richmond's climate makes easy. Because winters here never stress a heat pump's cold-weather performance, an aging gas furnace at end of life is often better replaced with a heat pump than repaired again. We run that math on the written estimate, including any rebates that apply, so you can compare repair cost against replacement instead of guessing.

The furnace turns on but only blows cold air. What does that mean?

It usually means the burners aren't lighting or aren't staying lit while the blower still runs. The common culprits are a cracked igniter, a dirty flame sensor shutting the burner down seconds after it fires, or a gas valve that isn't opening. All three are repairs, not replacements. We diagnose which one it is before quoting.

Nearby and related

Furnace Not Heating near Richmond: Berkeley · Oakland .

This is usually a furnace repair in Richmond job. See our furnace repair overview or the Richmond service area.