High
no live supply on red lead on Ideal Classic NF

Your boiler has lost power to an internal safety sensor, meaning it cannot start the ignition process for your heating or hot water.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

No live supply on the red lead to pressure switch; check PC Board supply/connections.

Engineer required

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

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