Emergency
VALVE FEED BACK ERROR on Johnson Starley Quantec C

Your boiler has detected that a component responsible for controlling the gas supply is not responding correctly, so it has safely shut down to prevent any risk.

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 feedback signal mismatch or resistance error

From this model's manual
Verified against the Johnson Starley Quantec C 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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