Low
31 on Ferroli Optimax 25 C

Your boiler is temporarily pausing its operation to protect itself because it has detected an unusual temperature reading, but it should restart on its own once it cools down.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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.

What the manual says

Manufacturer manual

Temporary shutdown fault - resets automatically as soon as the value comes back within the boiler’s normal working range

From this model's manual
Verified against the Ferroli Optimax installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

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

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