DHW sensor fault Low

Heatline DHW sensor fault Fault Code

Also written as DHWSENSORFAULT — same fault.

The Heatline DHW sensor fault fault code means: your boiler has detected a faulty sensor responsible for hot water temperature, so it is now running in a restricted 'backup' mode to ensure you still have hot water available.. It appears on 2 Heatline models in our database.

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description: If there is a fault on DHW sensor, system continues operation by controlling DHW outlet temperature by flow sensor and CH sensor, which limits the temperature up to 65ºC during DHW operation. Displays on LED screen.
Typical repair cost £120-200 (including labour)

Engineer required

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

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Heatline models that show the DHW sensor fault fault code

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

Source

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

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