High Lockout
E83466 on Potterton Powermax HE

Your boiler has detected an internal communication error, meaning the main control system and the display panel are struggling to talk to each other.

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

Boiler Control On/Off Switch

What causes this fault?

This fault occurs when the data link between the boiler's main brain and the display screen becomes corrupted or broken. The most common reason is an electronic component failure on one of the circuit boards or a loose connection in the internal wiring harness. It essentially means the boiler can no longer receive instructions on when to turn on or off.

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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