X00 Low

Remeha X00 Fault Code

The Remeha X00 fault code means: your boiler is currently set to a special configuration mode used by engineers for testing or setup, rather than operating in normal heating mode.. It appears on 3 Remeha 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: Setting mode service level
Typical repair cost £90-150 (including labour)

Engineer required

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

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Remeha models that show the X00 fault code

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

Source

Remeha X00 fault code information on this page is sourced and cross-checked against the official Remeha service / installation manuals for each affected model.

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