High Lockout
30 on Intergas Compact HRE OV

Your boiler's internal control board cannot safely communicate with the gas valve, preventing the system from igniting for your heating and 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

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 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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