High
lockout on Ravenheat CSI

Your boiler has detected that it is getting too hot and has safely switched itself off 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

An overheat cut off thermostat set slightly higher than the high limit thermostat acts to turn off the burner to resetable "lockout" (Fig. 50) 3.

From this model's manual
Verified against the Ravenheat He 80 90 25 30s Combi 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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