High
CONDITION 1 on Keston R-sm 20 FB

Your boiler has detected a fault and has safely shut itself down to prevent damage, leaving you without heating and hot water.

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.

Technical description

Red light on the instrument panel on (shut down signal)

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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Related fault codes

CONDITION 2View →CONDITION 3View →

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