Emergency
F.88 on Vaillant ecoTEC Plus 610

Your boiler has lost its connection to the component that controls the gas flow, meaning it cannot ignite safely to provide heating or hot water.

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

Fault: Gas valve. Gas valve not connected or it is connected incorrectly, short circuit in the cable harness

From this model's manual
Verified against the Vaillant Ecotec Plus 610 installation & service manual, page 34.
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

F.28View →F.29View →

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