Emergency
285 on Navien NCM 1130HH

Your boiler has detected an electrical short circuit on the internal circuit board or main wiring connection.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

What the manual says

Manufacturer manual

285:Alternat SC

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.

Engineer required

This is a emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

280View →281View →

All 77 fault codes on the NCM 1130HH

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

96979899100102114116117118121122127157158164187253254257258259260261262263264265266267268269270271272273274275276277278280281282283284286287288289290291292293294295296298299300301302303304305306307308309310311319394395396397

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