High
Overheat Detection on Chaffoteaux Talia Green 25

Your boiler has automatically turned itself off because it detected that the water inside has become dangerously hot.

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

If a temperature over 100°C is detected in the primary circuit by the sensor 23, the safety solenoids close and the fan stops. It is possible to reset the boiler when the primary circuit temperature falls below 76°C.

From this model's manual
Verified against the Chaffoteaux Talia Green 25 installation & service manual.
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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