24 Low

Sime 24 Fault Code

The Sime 24 fault code means: your boiler has lost the connection to the temperature sensor responsible for reading your solar water heating panel, which may cause your solar system to stop working temporarily.. It appears on 2 Sime 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: SOLAR S1 COLLECTOR PROBE FAILURE
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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Sime models that show the 24 fault code

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

Source

Sime 24 fault code information on this page is sourced and cross-checked against the official Sime service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026