Low
353 -- on Worcester Bosch Greenstar CDi Compact

Your boiler has automatically locked itself out temporarily because it has been running non-stop for too long, but it will reset itself and start working again shortly.

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

Wait patiently for approximately 20 minutesEnsure your thermostat settings are not requesting heat constantlyDo not attempt to open the boiler casing

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