High
AL79 on Vokera Easi Heat Plus 18

Your boiler has shut down because the water inside it is getting too hot, too quickly, often because it cannot circulate properly through your radiators.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

Flow temperature too high, or temperature differential between primary and return too high

From this model's manual
Verified against the Vokera Easi Heat Plus 18 installation & service manual, page 29.
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 high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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