1 to 9 Low

Remeha 1 to 9 Fault Code

Also written as 1TO9 — same fault.

The Remeha 1 to 9 fault code means: your boiler is currently running normally and is in the process of heating up or waiting for a demand for hot water.. It appears on 1 Remeha model 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: Operating codes (see Par. 6.3)

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 1 to 9 fault code

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

Source

Remeha 1 to 9 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 7 July 2026