How much does it cost to fix Daikin error code HJ-10?

Typical repair cost for the Daikin HJ-10 fault is £140-£260 including labour.

HJ-10 High

Daikin HJ-10 Fault Code

Q: What does the Daikin HJ-10 fault code mean?

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

Also written as HJ10 — same fault.

The Daikin HJ-10 fault code means: your boiler has lost the ability to accurately measure the water pressure, which prevents it from operating safely to heat your home.. It appears on 1 Daikin model in our database.

Technical description: Water pressure sensor fault

What causes the Daikin HJ-10 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.

Typical repair cost £140-£260 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Daikin models that show the HJ-10 fault code

Click a model for the full fault code list and model-specific repair notes.

D2CND Repair: £140-£260

Source

Daikin HJ-10 fault code information on this page is sourced and cross-checked against the official Daikin service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026