BoilerFaultCodesYour boiler's internal control board cannot safely communicate with the gas valve, preventing the system from igniting for your heating and hot water.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Gas valve relay faulty
What causes this fault?
This fault occurs when the boiler's main control board detects a hardware failure in the electrical relay that manages the fuel supply. It means the system can no longer safely open or close the gas valve, so it shuts down as a protective measure to ensure gas cannot flow uncontrollably. The root cause is typically a component failure on the printed circuit board itself or a communication breakdown between the board and the gas valve.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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