Low
353 on Worcester Bosch 24/28/35 CDi MkII

Your boiler has detected that it hasn't had a proper rest period in the last day and is temporarily pausing to protect itself from excessive wear.

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

Burn temporarily blocked due to no 20 minute continuous OFF time in last 24 hours.

From this model's manual
Verified against the Worcester Bosch Greenstar Cdi Compact installation & service manual, page 66.
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

Switch the boiler off at the fused spur or mains power for 30 secondsTurn the power back on to reset the system's internal timerEnsure your heating programmer is set to allow for natural standby periods during the night

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