How much does it cost to fix Ferroli error code LED 4 (A)?

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

LED 4 (A) High

Ferroli LED 4 (A) Fault Code

Q: What does the Ferroli LED 4 (A) fault code mean?

Your boiler has stopped providing hot water because it is struggling to read or regulate the temperature from its water heating sensor.

Also written as LED4A — same fault.

The Ferroli LED 4 (A) fault code means: your boiler has stopped providing hot water because it is struggling to read or regulate the temperature from its water heating sensor.. It appears on 1 Ferroli model 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 (A) fault code

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

Hawk II Repair: £120-220

Source

Ferroli LED 4 (A) 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