BoilerFaultCodesWhat the manual says
Manufacturer manualFaulty air pressure switch
From this model's manual
Verified against the Biasi/Biasi Service Manual M96 24 Sm P installation & service manual.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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All 13 fault codes on the Parva 28S
Seeing a different code? Every code this model can display, in one place.
Excessive temperature on primary circuitFaulty c.h. temperature probe NTCFaulty d.h.w temperature probe NTCFaulty Electronic control/ignition p.c.b.Faulty flue temperature probe NTCFaulty primary circuitFaulty primary circuit (no water or absence of flow)Flue temperature probe NTC lockoutLack of burner ignitionLack of power supplyLack of power supply or faulty electronic control p.c.b.Safety thermostat lockout