BoilerFaultCodesWhat the manual says
Manufacturer manualGas safety valve failure
From this model's manual
Verified against the Glow Worm 30ci Plus installation & service manual, page 39.
What causes this fault?
This fault occurs when the boiler's control board sends a signal to open the gas valve, but it doesn't receive the correct electrical feedback to confirm it has happened. The most common reason is an internal mechanical failure of the gas valve itself, or a communication breakdown caused by a faulty circuit board or loose wiring connections.
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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