High Lockout
F.60 on Vaillant Turbomax Plus VUW 242EH

Your boiler has detected an internal electrical fault 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 electrical communication with the gas valve or detects an incorrect voltage return. The most common reason is an internal electronic failure within the gas valve itself or a fault on the circuit board that prevents it from sending the correct signal to release gas.

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.61View →F.62View →F.27View →

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