Emergency
A 04 on Vokera Verve I 50

Your boiler has automatically turned itself off because it has detected that it is running much hotter than it should be.

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

Possible safety thermostat intervention due to overheating.

From this model's manual
Verified against the Vokera Verve I 50 installation & service manual, page 32.
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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Related fault codes

A 02View →A 03View →

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