High Lockout
HJ-10 on Daikin D2CND

Your boiler has lost the ability to accurately measure the water pressure, which prevents it from operating safely to heat your home.

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

Water pressure sensor fault

What causes this fault?

This fault occurs when the internal electronic sensor responsible for monitoring water levels becomes faulty or sends an incorrect signal to the main control board. The most common reason is an internal component failure within the sensor itself or a loose connection in the wiring that links the sensor to the boiler's computer.

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

HJ-08View →

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