Furnace Standing Pilot Light Troubleshooting Guide

Published: July 23, 2026 — BC Wide Home Services Ltd, doing business as BC Wide Heating & Air Conditioning — Greater Vancouver, BC

Thermocouple Function

The thermocouple is a safety device that detects if the pilot flame is lit. If it fails, the gas valve closes, extinguishing the pilot. Replace the thermocouple ($20-50 part, $150-250 installed) if the pilot lights but goes out when you release the button.

Other Common Causes

Draft blowing out the pilot (check for nearby doors or vents), dirty pilot orifice restricting the flame (clean with compressed air), or weak gas pressure (requires professional measurement). A dirty pilot flame that is mostly yellow indicates partial blockage.

When to Upgrade

If your furnace is over 20 years old with a standing pilot, consider upgrading to a modern electronic ignition furnace. Standing pilot furnaces waste gas (the pilot burns 24/7) and lack modern safety features and efficiency.

Related Services

Safety Reminder

If you smell gas, suspect carbon monoxide or believe there is an immediate danger, leave the property and contact emergency services or the appropriate gas emergency authority. Do not remain inside — exit the building immediately and call for help from outside.