High
Relay 2 energised after 2 sec on Ferroli Combi 77 FF Popular

Your boiler has detected an internal electrical or sensor error that is preventing it from starting up safely.

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

Check water flow switch D.H.W., D.H.W. temperature sensor 34, Central heating relay, or replace P.C.B.

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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