High Lockout
E83486 on Potterton Powermax HE

Your boiler has detected a communication problem or a electrical fault with the sensor that monitors water pressure, which has caused the system to stop working 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

Pressure Sensor ‘Ranco’Black

What causes this fault?

This fault occurs when the boiler's main control board loses electrical contact with the sensor that monitors water pressure. The most common reason is a physical failure within the Ranco sensor itself or a loose connection in the wiring harness that links the sensor to the brain of the boiler.

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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Related fault codes

A01View →

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