How to Fix a Boiler Pilot Light That Has Gone Out

Overview

A boiler pilot light that has gone out can leave you without heating. This guide covers relighting the pilot light safely.

Step-by-Step Fix

1. First, locate the gas shut-off valve for your boiler, which is usually a red or yellow lever or tap on the gas supply pipe leading to the appliance. Turn this valve to the 'off' position and wait for at least five minutes to allow any residual gas to dissipate safely. This crucial step prevents gas from building up while you are working near the pilot light.
2. Next, identify and open the access panel or cover that shields the pilot light assembly; consult your boiler's manual if you're unsure of its exact location. This panel is often secured by clips or small screws and must be carefully removed to expose the pilot light and relighting controls. Take care not to force it and ensure the area is clear before proceeding.
3. Refer directly to your boiler's manufacturer instructions, typically found on a label inside the access panel or in the user manual, for the precise relighting procedure. Generally, this involves pressing and holding a reset button, then simultaneously pressing an igniter button while observing the pilot light. Continue holding the reset button for about 20-30 seconds after the pilot lights to allow the safety mechanism to heat up.
4. If the pilot light ignites but then extinguishes shortly after you release the reset button, it strongly suggests a fault with the thermocouple. This small safety device is designed to detect the pilot flame and maintain gas flow, and if it's not working correctly, the boiler will automatically shut off the gas as a safety measure. Observe carefully whether the flame holds or immediately goes out after you've held the button for the recommended time.
5. If you are a Gas Safe registered engineer, and you have identified a faulty thermocouple, you may proceed with its replacement following manufacturer guidelines. Ensure the main gas supply to the boiler is off and isolate the electrical supply before commencing any work. This is a regulated task that must only be undertaken by a qualified professional to ensure safety and compliance.
6. If you are in any doubt about the cause of the pilot light failure, are not confident in carrying out the procedure, or if the pilot light repeatedly goes out, do not attempt further repairs yourself. Immediately turn off the gas supply to the boiler and contact a Gas Safe registered engineer. They have the expertise and tools to diagnose and safely rectify the issue, ensuring your boiler operates safely and efficiently.

Common Symptoms & Diagnostic Resolutions

Review the common error codes and operating symptoms below to quickly identify the root cause of the fault before ordering replacement parts.

Frequently Asked Questions