High
Safety Thermostat Neon on Baxi System 35/60 / 60/100

Your boiler has detected that it is getting too hot and has automatically switched itself off to prevent any damage or safety issues.

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

Shuts down the boiler in the event of the system or the boiler overheating.

From this model's manual
Verified against the Baxi System 35 60 60 100 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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