Medium
2940 on Worcester Bosch Greenstar 27CDi

Your boiler is struggling because it is not receiving the correct amount of electrical power, which is likely due to a poor connection or a minor electrical fault.

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Low voltage

From this model's manual
Verified against the Worcester Bosch Greenstar 27cdi installation & service manual, page 86.
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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Avoid the next call-out bill

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