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.

Technical description

Fault:Gasvalve | Gasvalvenotconnectedoritisconnectedincorrectly,shortcircuitinthecableharness

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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