Vokera boiler troubleshooting



Most boilers stop working due to external factors rather than due to faulty designs. A malfunction must be diagnosed and eliminated, and you can do that using the troubleshooting table below. It describes the most common causes of malfunctions, and there are solutions in the opposite column.

VOKERA Mynute VHE boiler troubleshooting

CODECAUSEALARM TYPEACTION
AL10Ignition failure/not flame sensed, condense sensor activatedFinalReset, check appliance operation
AL20Limit thermostat fault
AL21External device fault (UHT/CPA)Reset, check appliance
AL26Return temperature too highReset, check pump, ensure there is sufficient flow sensor temperature), circulation around heating circuit/s
AL28Temperature differential inverted (return sensor temperature higher than flowsensor temperature)Reset, check pump, ensure there is sufficient circulation around heating circuit/s thermistors
AL34Fan tacho signal faultReset check appliance operation, check fan
AL52Internal faultReset, check appliance operation
AL55Jumper tag faultCheck jumper tag configuration
AL60Temporary
AL71Primary (flow) thermistor faultCheck primary thermistor, check wiring
AL73Return thermistor faultCheck return thermistor, check /wiring
AL74No water circulationFinalReset, check appliance operation, check pump, ensure there is water and sufficient circulation around heating circuit/s
AL79Flow temperature too high, or temperature differential between primary and return too highReset, check appliance operation, check thermistors

VOKERA Option boiler troubleshooting

FaultPossible causesRemedy
Appliance fires then lockoutsIncorrect gas pressure flue blocked or brokenCheck incoming pressure and/or burner pressures check flue assembly
Appliance wont fire for hot waterHot & cold pipes reversed flow regulator blocked insufficient flow rateCheck external plumbing remove and clean increase flow rate
Appliance wont fire for heatingExternal control or wiring fault or wiringCheck external controls
Appliance fires for heating but no circulation around systemFlow & return service valves closed air in appliance pump stuckOpen service valves open dustcap on ‘aav’ open vent plug on pump and rotate shaft flush system
Debris in system
Appliance inactive no ‘led’s showingElectrical supply fault blown fuseCheck supply to appliance for 240v between ‘l’ & ‘n’ check and replace

VOKERA Vision 25C boiler troubleshooting

ALARM CODECAUSEALARM TYPEACTION
StAUTOSTOPFinalCall engineer
_CLCALL FOR SERVICETemporary then Final
A01Ignition failure, flame not sensed, internal faultFinalReset, check appliance operation
A02Limit thermostat fault
A03Fan tacho signal faultReset check appliance operation, check fan
A04Insufficient system water pressureCheck/refill system pressure, reset, check appliance operation
A06DHW thermistor faultTemporaryCheck DHW thermistor
A07Primary (flow) thermistor faultTemporaryCheck primary thermistor, check wiring
Primary (flow) thermistor over temperatureTemporary then FinalReset, check appliance operation
Temperature differentialFinalReset, check appliance operation, check thermistors
A08Return thermistor faultTemporaryCheck return thermistor, check wiring
Return thermistor over temperatureTemporary then FinalReset, check appliance operation
Temperature differential invertedFinalReset, check pump, ensure there is sufficient circulation around heating circuit/s
A09Flue thermistor or flue thermistor counter faultTemporaryCheck flue thermistor counter at power on, check flue thermistor, check wiring
Flue thermistor over temperatureFinalReset, check appliance operation
A77Low temperature thermostat faultTemporaryCheck low temperature thermostat
AdjCalibrationNaNone
ACOService operation
PPreheating function active
P blinkingPreheating function running
FlameFlame ON
HoursStand-by
OFF