High
356 on Worcester Bosch Greenstar 2000

Your boiler is struggling because the electricity supply it is receiving is weaker than it needs to operate reliably.

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

Power supply for the boiler is too low

From this model's manual
Verified against the Worcester Bosch Greenstar 27cdi installation & service manual, page 82.
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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