Low
270 on Worcester Bosch Greenstar Heatslave II

Your boiler is simply performing a routine safety check as it starts up, which is a normal process that happens every time it is switched on.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

Power up mode: The boiler is ON, warming up and running self check routines. This lasts approximately 35seconds.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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