High Lockout
E130 on Potterton Assure Combi / System

Your boiler has shut down because a safety sensor has detected that the exhaust gases are getting too hot, which can be caused by a blockage or an internal component failure.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

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

Technical description

Flue thermostat sensor tripped and locked out

What causes this fault?

This fault occurs when a safety sensor detects that the exhaust gases leaving your boiler have reached a dangerously high temperature. It is usually caused by a build-up of debris or limescale inside the main heat exchanger, which prevents heat from being transferred to your water and instead sends it out through the flue. In some cases, the sensor itself may have failed or there could be a blockage in the chimney preventing the hot air from escaping.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

E110View →

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