Low
35 on Ferroli Optimax

Your boiler has detected an unusual signal or flame when it shouldn't have and is pausing for a short time to keep itself safe.

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

Check if any nearby gas appliances were being used heavily at the same timeWait up to 10 minutes to see if the boiler resets itself automaticallyLocate the reset button and press it once if the code does not clear on its own

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