High Lockout
H00269 on Potterton Powermax HE

Your boiler has detected a problem with the internal sensor that monitors water pressure, preventing it from heating your home or water safely.

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 Transmitter ‘Huba’Red

What causes this fault?

This fault occurs when the internal sensor responsible for monitoring water pressure fails to send a reliable signal to the boiler’s main control board. The most common reason is that the sensor has developed an electrical fault or has become blocked with debris from the heating system, making it impossible for the boiler to confirm there is enough water to operate safely.

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

A02View →E08View →

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