High Lockout
E09 on Potterton Powermax HE

Your boiler has detected an electrical issue with the component that controls the gas supply, causing the system to shut down for safety.

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 / Board Error - Internal control or valve feedback error

What causes this fault?

This fault occurs when the boiler's main control board loses communication with the gas valve or detects an incorrect electrical signal between them. The most common reason is a component failure within the gas valve itself or a fault on the printed circuit board that prevents it from safely managing the fuel supply.

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.

Find a Gas Safe engineer
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Related fault codes

E08View →A01View →

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