High
E07 on Keston C36p

Your boiler has detected that the exhaust gases are becoming dangerously hot, so it has safely shut itself down to prevent internal heat damage.

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.

What the manual says

Manufacturer manual

Flue overheat - check combustion and flue temperature vs. return temperature (Installer numbers 7 and 3 above). The flue temperature should be no more than 10C above return temperature. Possible heat exchanger fault

From this model's manual
Verified against the Keston C36p installation & service manual, page 32.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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