Furnace Vent Limit Switch Replacement in Vancouver

Published: July 22, 2026 — BC Wide Home Services Ltd, doing business as BC Wide Heating & Air Conditioning — Greater Vancouver, BC

Purpose of the Vent Limit Switch

The vent limit switch is a safety device on some furnaces that monitors flue gas temperature. If the vent becomes partially blocked, flue gases get hotter than normal, and the switch shuts down the furnace to prevent flue damage and carbon monoxide leakage.

Signs of Failure

The furnace shuts off frequently, the switch trips and requires manual reset, the flue pipe feels hotter than normal near the switch, or the switch tests out of specification (opens or closes at wrong temperature). A tripping vent limit switch indicates a venting problem.

Replacement Cost

Vent limit switch replacement costs $250-450 including the part ($30-80) and labour ($150-$250). If the switch keeps tripping after replacement, the venting must be inspected for blockages, damage, or improper sizing.

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.