High
Too Many Restarts on Keston C30 / C35

Your boiler has attempted to restart itself multiple times in a short window because it keeps encountering a recurring problem, and it has now locked itself out to prevent 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

The boiler attempted to restart 5 times within 15 minutes

From this model's manual
Verified against the Keston C30 C35 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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