No Heat in Kootenai, ID

Here are the most common root causes we find on no-heat calls:

1. Failed Igniter The hot surface igniter is a fragile ceramic element that glows red-hot to light the burners. It's one of the highest-failure components in a gas furnace. When it cracks or burns out, the burners never light - the blower runs, but you get cold air.

2. Tripped Limit Switch The high-limit switch is a safety device. When the furnace overheats - usually due to restricted airflow - it shuts off the burners to protect the heat exchanger. The blower keeps running to cool things down, which is why you feel air but no heat. A dirty filter is the most common trigger. But a limit switch that trips repeatedly points to a deeper airflow or heat exchanger problem.

3. Pressure Switch Failure The pressure switch confirms that the inducer motor (the fan that vents combustion gases out of the flue) is working before allowing the burners to light. If the switch fails, or if there's a blockage in the flue or condensate drain, the furnace locks out. This is a safety interlock - it's doing its job. But it needs a proper diagnosis to find out why it tripped.

4. Flame Sensor Fouled or Failed The flame sensor is a small metal rod that sits in the burner flame. It sends a signal to the control board confirming combustion is happening. When it gets coated with oxidation over time, it can't read the flame reliably. The board shuts the gas valve as a safety measure. The burners light briefly, then go out. You get a few seconds of heat, then cold air again.

5. Control Board Fault The control board is the brain of the furnace. It sequences every step of the startup cycle. When it fails - due to age, a power surge, or a component failure - it can interrupt the heating cycle at any point. Diagnosing a board fault requires ruling out every upstream component first. Replacing a board without that process is expensive guesswork.

6. Gas Supply Issue If the gas valve isn't opening, or if there's an interruption in supply, the burners simply won't light. This can be a failed valve, a pressure issue at the meter, or a safety lockout triggered by a prior fault.

> If you smell rotten eggs or sulfur at any point, stop. Leave the home immediately. Contact your gas utility and emergency services.

Before you call, run through these checks. They take five minutes and occasionally solve the problem entirely.

• Check your thermostat. Make sure it's set to HEAT, not COOL or FAN ONLY. Set the temperature at least 5°F above the current room temperature. Replace the batteries if it's been over a year.
• Check your filter. A clogged filter is the single most common cause of furnace lockouts. If it's gray and packed with debris, replace it. Then reset the furnace by switching it off at the thermostat for 30 seconds and back on.
• Check your circuit breaker. Furnaces run on electricity even if they burn gas. A tripped breaker cuts power to the control board and blower. Reset it once. If it trips again, stop - that's a sign of a wiring or motor fault.
• Check the furnace power switch. It looks like a light switch, usually on the wall near the unit or on the unit itself. Make sure it's on.
• Check the flue vent (exterior). If you can safely see the exhaust vent on the outside of your home, check that it isn't blocked by snow, ice, or debris. A blocked flue will cause a pressure switch lockout.
• Look at the furnace status light. Most modern furnaces have a small LED that blinks a fault code. Count the blinks and check the code chart (usually on the inside of the furnace door panel). This gives us useful information when you call.

If none of these resolve the issue, it's time to call.