High Lockout
F.61 on Vaillant Turbomax Plus VUW 242E

Your boiler has detected an electrical communication problem with the gas valve, which means it cannot safely light the flame to provide heating or hot water.

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.

Technical description

Electronic fault | Electronics defect

What causes this fault?

This fault occurs when the boiler's main control board loses the ability to send or receive electrical signals to the gas valve. The most common reason is an internal electronic failure within the circuit board itself, though it can also be caused by loose wiring or a faulty solenoid on the gas valve. Because the boiler cannot safely regulate the flow of gas, it shuts down immediately as a safety precaution.

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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Related fault codes

F.62View →F.27View →

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