BoilerFaultCodesWhat the manual says
Manufacturer manualSafety thermostat lock out
From this model's manual
Verified against the Biasi/Biasi Riva Advance M96 24sm installation & service manual.
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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Related fault codes
All 13 fault codes on the Riva Advance HE M110B.24SR/C
Seeing a different code? Every code this model can display, in one place.
Excessive temperature on primary circuitFaulty c.h. temperature probe NTC.Faulty d.h.w temperature probe NTCFaulty Electronic control/ignition p.c.b.Faulty external temperature probe NTCFaulty fan control systemFaulty primary circuitFlame detection errorFlue temperature probe NTC lock outLack of burner ignitionLack of power supply or faulty electronic control p.c.b.Open flue temperature probe NTC