High
Overheat detection on Chaffoteaux 80/100

Your boiler has shut itself down because it detected that it is running too hot, indicating a potential circulation or sensor problem.

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

If an overheat is detected by the sensor (13), the grey security solenoid (30) and the blue 1/3 (31) closes, the orange indicator lamp (21) extinguishes. The ignitor is energised for 8 seconds and the red lockout indicator (22) lights.

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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