BoilerFaultCodes.com
08 High Lockout

Your boiler has shut down because a specific safety sensor on the burner has detected that it is getting too hot.

Call an engineer soon

Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description: Fault code 08 appears if the burner thermostat has been activated. (only for 35e)

What causes this fault?

This fault occurs when a safety sensor detects that the metal housing around the burner is reaching dangerous temperature levels. It is usually caused by a lack of water flow through the heat exchanger or a build-up of debris blocking the internal ports, which prevents heat from being carried away quickly enough. In some cases, the sensor itself may have failed or the wiring has become damaged due to the high heat environment.

Typical repair cost £100-250 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Protect yourself from future repair bills

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