How do I check my furnace ignitor?

A faulty ignitor is one of the most common reasons furnaces won't start, but checking it requires caution since you'll be working near gas components. Always turn off power to your furnace at the electrical panel before beginning any inspection.

Visual inspection is the safest approach for homeowners. Remove the furnace access panel (usually held by screws or clips) and locate the ignitor - it looks like a small ceramic or silicon carbide element, similar to a glowing coil. Look for obvious cracks, breaks, or burn marks on the ignitor itself. A cracked ignitor will need replacement even if it still glows, as it won't generate enough heat to reliably light the gas.

The glow test can help confirm ignitor function, but should be done carefully. With the power restored, set your thermostat to call for heat and observe the ignitor through the access panel opening. A working ignitor should glow bright orange or white-hot within 30-60 seconds. If it doesn't glow at all, glows dimly, or takes longer than 90 seconds to reach full brightness, it's likely failing. However, never attempt to touch or remove the ignitor yourself - these components are fragile and gas appliance work requires a licensed G2 technician under TSSA regulations.

In Ottawa's climate, ignitors typically last 3-7 years depending on usage. If your furnace is cycling on and off without producing heat, or you hear the draft motor running but no ignition occurs, a faulty ignitor is often the culprit. Professional replacement usually costs $200-400 including the service call.

If you suspect ignitor problems, turn off your furnace and call for service rather than repeatedly attempting to restart it. Multiple failed ignition attempts can be dangerous and may damage other components. For reliable furnace repair in Ottawa, contact a TSSA-licensed technician who can safely diagnose and replace the ignitor.