Emergency
E80-451 on Worcester Bosch 24/28/35 CDi MkII

Your boiler has detected an issue with its internal gas supply system which is preventing it from heating your home safely.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

What the manual says

Manufacturer manual

Gas Valve – Propane

From this model's manual
Verified against the Worcester Bosch/Worcester Bosch 24 28 35 Cdi Mkii Rsf installation & service manual.
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 emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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All 27 fault codes on the 24/28/35 CDi MkII

Seeing a different code? Every code this model can display, in one place.

ABCDEE00 716E00-711E00-716E00-720E00-721E00-730E00-737E00-738E00-741E01 612E01-840E80-450FGHIJKtaehrevO yramirPtluaF rosneStuokcoL renruB

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