How much does it cost to fix Ferroli error code LED 4 (D.H.W.)?

Typical repair cost for the Ferroli LED 4 (D.H.W.) fault is £120-220 including labour.

LED 4 (D.H.W.) High

Ferroli LED 4 (D.H.W.) Fault Code

Q: What does the Ferroli LED 4 (D.H.W.) fault code mean?

Your boiler has stopped producing hot water because it has lost contact with or is misreading the temperature sensor that monitors your hot water supply.

Also written as LED4DHW — same fault.

The Ferroli LED 4 (D.H.W.) fault code means: your boiler has stopped producing hot water because it has lost contact with or is misreading the temperature sensor that monitors your hot water supply.. It appears on 2 Ferroli models in our database.

Technical description: D.H.W. sensor (42) not connected or D.H.W. temperature too high.

Typical repair cost £120-220 (including labour)

Engineer required

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

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Ferroli models that show the LED 4 (D.H.W.) fault code

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

Source

Ferroli LED 4 (D.H.W.) fault code information on this page is sourced and cross-checked against the official Ferroli service / installation manuals for each affected model.

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