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.

What the manual says

Manufacturer manual

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

From this model's manual
Verified against the Worcester Bosch Greenstar Heatslave Ii installation & service manual, page 29.
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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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