Low
40 on Ferroli Optimax

Your boiler has paused temporarily because it has detected an unusual reading, but it should restart itself automatically once the system settles 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.

DIY fix possible

Wait up to 15 minutes to see if the boiler clears the code and restarts itselfCheck that your radiators are bled and there is no trapped air in the systemEnsure the central heating system pressure is between 1.0 and 1.5 bar

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