No Heat in Spokane Valley, WA

Spokane Valley has seen a lot of residential construction over the past 15–20 years. Many of those homes were built with builder-grade furnaces that are now hitting the 15-to-20-year mark - right at the edge of their designed lifespan. That matters because component failures cluster at this age.

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

Ignition system failure. Most modern furnaces use either a hot surface igniter (a fragile ceramic element) or an electronic ignition. When the igniter cracks or the ignition control fails, the burners never light. The blower may still run - pushing unheated air through your vents.

Flame sensor fouled or failed. The flame sensor is a small rod that confirms the burner actually lit. If it's coated in oxidation, it can't read the flame correctly and shuts the gas valve off within seconds of ignition. The furnace may short-cycle - starting, then stopping - or produce no heat at all.

Gas valve not opening. The gas valve controls fuel flow to the burners. A failed valve - or a valve that's not receiving the correct signal from the control board - means no fuel, no flame, no heat.

Control board failure. The control board is the brain of the furnace. It sequences every step: call for heat → inducer on → pressure switch confirmed → igniter energized → gas valve opens → flame confirmed → blower on. A fault anywhere in that logic can stop heat production cold.

Pressure switch stuck open or failed. The pressure switch confirms that the inducer motor is creating proper draft before allowing ignition. A failed inducer motor, a cracked pressure switch hose, or a blocked condensate drain can all cause the pressure switch to stay open - locking out ignition entirely.

Overheated heat exchanger triggering the high-limit switch. If airflow is restricted - dirty filter, blocked registers, undersized ductwork - the heat exchanger overheats and the high-limit switch cuts the burners. The blower keeps running to cool things down, but you get no heat. Repeated high-limit trips can crack the heat exchanger over time.

Thermostat or wiring issue. Less dramatic, but real. A misconfigured thermostat, a dead battery in a wireless stat, or a wiring fault between the stat and the furnace can prevent the call-for-heat signal from ever reaching the control board.

Before you call, run through these checks. They take five minutes and occasionally solve the problem without a service visit.

• Check the thermostat setting. Confirm it's set to HEAT, not COOL or FAN ONLY. Set the temperature at least 5°F above the current room temp to trigger a heat call.
• Check the filter. A severely clogged filter can cause the furnace to overheat and trip the high-limit switch. If the filter is gray and matted, replace it before resetting the furnace.
• Check the circuit breaker. The furnace should have a dedicated breaker. If it's tripped, reset it once. If it trips again, stop - that's an electrical issue that needs diagnosis.
• Check the furnace power switch. There's usually a wall switch near the furnace that looks like a light switch. Confirm it's in the ON position.
• Check the condensate drain (high-efficiency furnaces). If your furnace has a white PVC exhaust pipe, it's a high-efficiency unit with a condensate drain. A clogged drain can trigger a safety shutoff. Look for standing water near the furnace base.
• Check for error codes. Many furnaces have a small LED on the control board that flashes a fault code. Count the flashes and check the code chart (usually on the inside of the furnace door panel).

If none of these resolve the issue, it's time to call. Don't keep resetting a furnace that keeps locking out - you may be masking a safety fault.