Medium
E077 on Vokera Unica MAX Combi

Your boiler has detected an issue with the sensor that monitors the temperature of the water in your main heating circuit, which may prevent your radiators from warming up correctly.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Main zone water thermostat

From this model's manual
Verified against the Vokera Unica Max Combi installation & service manual, page 9.
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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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