High
Err HJ-09 on Daikin D2TND024

Your boiler has temporarily stopped working because the water pressure inside the system has dropped too low.

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.

What the manual says

Manufacturer manual

Due to low pressure, error code appears on the user interface and the status indicator light will be red

From this model's manual
Verified against the Daikin/Daikin D2tnd024 Combi installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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