Medium
34 on Ferroli Optimax

Your boiler has temporarily paused because the electrical voltage supplied to it is currently too low for it to operate safely.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

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 there is a local power cut or grid fluctuation in your areaSwitch off and unplug heavy-duty electrical appliances that may be overloading the circuitMonitor the boiler to see if it restarts automatically once the supply voltage stabilizes

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