Low
270 on Worcester Bosch Greenstar 12i System

Your boiler is simply performing a routine internal check-up as it starts up or resets, which is a normal process.

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. Appliance is initialising.

From this model's manual
Verified against the Worcester Bosch Greenstar 12i System installation & service manual, page 63.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Wait 5 minutes to allow the boiler to complete its automated startup sequence.If the code persists, perform a system reset by holding the reset button for 3 seconds.If it still does not return to normal operation, switch the boiler off at the fused spur for 1 minute and turn it back on.

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