Medium
309 on Navien NCM 1130HH

Your boiler has detected an interruption in its electrical power supply.

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

A power failure condition has been detected by the microcontroller supervisor.

From this model's manual
Verified against the Navien/Navien Ncm 1130hh 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 that the boiler's fused spur switch on the wall is turned on.Check your home's main fuse box (consumer unit) to see if a trip switch has activated.Reset the boiler by turning it off and on again if power was recently restored.

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Related fault codes

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All 77 fault codes on the NCM 1130HH

Seeing a different code? Every code this model can display, in one place.

96979899100102114116117118121122127157158164187253254257258259260261262263264265266267268269270271272273274275276277278280281282283284285286287288289290291292293294295296298299300301302303304305306307308310311319394395396397

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