BoilerFaultCodesWhat the manual says
Manufacturer manualExternal interlock circuit open
From this model's manual
Verified against the Ideal/Ideal Gc No 41 750 38a 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 34 fault codes on the Evomax
Seeing a different code? Every code this model can display, in one place.
16767778798081828384858687888990BCC FaultCylinder Thermistor FaultError 20False Flame LockoutFan FaultFlame LossFlow Thermistor FaultFlow/Return ReversedIgnition LockoutIgnition Lockout [16]Low Mains VoltageLow Water PressureOutside Sensor FaultOverheat LockoutPCB FaultReturn Thmr FaultToo Many Resets