High Lockout
EE5 on Worcester Bosch WR325 RSF

Your boiler's gas valve is not opening or functioning correctly, preventing the system from producing heat 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

Main valve

What causes this fault?

This fault occurs when the boiler's control system attempts to ignite the burner but detects that the gas valve has failed to open. The most common reason is an electrical failure within the valve's internal motor or a communication error from the main circuit board that prevents the flow of 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

EAView →E9View →

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