Alpha Boiler Error Codes

Alpha Boiler Error Codes

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Heating Engineer’s Toolkit
Fault CodeModel AffectedFaultPossible Cause
1AllIgnition failureGas supply
Check pressure tubes
Ignition electrode gap
Flame sensor electrode gap
Ignition generator or lead Flame sensor electrode lead
Gas valve setting
Gas valve PCB
2AllOverheat boiler lock outPump or flow problem
Blocked heat exchanger
Air in heat exchanger
Overheat thermostat
Thermal fuse (if open circuit then replace primary heat exchanger)
3AllHigh flue thermostat temperatureBlocked or restricted primary flow
Heat exchanger air flow blocked
Flue restriction
Flue sensor fault
4AllGas valve electrical connection faultGas valve lead connection fault
Faulty gas valve
Faulty PCB
5AllHeating flow sensor faultFlow sensor wire connections
Flow sensor faulty
6AllDHW sensor faultDHW sensor wiring connection
DHW sensor faulty
8AllMaximum number of resetsRefer to fault history codes
10AllPrimary system pressure lowCheck expansion vessel pressure (1 bar) Leak in system
Expansion relief valve operated
Primary pressure switch
12All“Cylinder sensor fault (FlowSmart only)”Cylinder sensor wiring connections
Cylinder sensor faulty
15AllInternal wiring errorCheck internal wiring connections to PCB Combination boiler DHW sensor X4 System boiler link X14 Refer to wiring diagram
16AllFan faultCheck fan wiring connections
Fan fault PCB fault
20AllFlame sensing faultCheck flame sensing electrode and lead
PCB fault
24AllControl panel button faultCheck for jammed control panel buttons
Check for jammed PCB buttons
25AllOverheat lock outAir in heat exchanger
Blocked or restricted primary flow
Heat exchanger air flow blocked
Flue restriction
Flue sensor fault Pump fault Boiler or Heating circuit valve closed
27AllInsufficient primary flowBlocked or restricted primary flow
Air in heat exchanger Boiler or heating circuit valve closed
Pump fault
Primary flow sensor fault
29AllFlue sensor faultCheck sensor wiring connection
Flue sensor faulty
31AllLoss of communication with external Control (Alpha Climatic)Remote control or receiver connection wiring
Remote control or receiver
37AllLow supply voltage
Check mains power supply
Check for bad cable connections etc
38All
Flame detected but signal lost. Ignition retries after fan purge
Check flame sensing electrode and lead
Check for flue gas recirculation
Check the gas valve
Check flue system and termination
Check gas supply/working pressure
Check/adjust combustion settings
43AllLoss of flame rectificationCheck gas supply/working pressure
Check flame sensing electrode and lead
Check for flue gas recirculation
Check/adjust the gas valve settings
Check/adjust the fan speed settings
44AllSafety lock outCheck external control (room thermostat) requests Rapid on/off hot tap requests
46AllExternal sensor interventionCheck external sensor and cable are not damaged or wet
Check continuity of external sensor and circuit
Check connection at X19 on PCB and sensor connecting block
47AllReduced burner outputAir in heat exchanger
Restricted primary flow
Heat exchanger air flow blocked
Flue restriction
Flue sensor fault Pump fault
51AllClimatic RF communication faultBatteries require replacing Distance between boiler and climatic control too great Interference Object blocking signal (metallic)
59AllMains supply voltage
frequency block
The PCB detects an incorrect mains supply
Voltage frequency – Check mains power supply
Faulty PCB
60AllPump fault
The pump is stuck or there is an electrical pump fault:
Check the pump operation, it may be necessary to free the pump shaft
Check the pump wiring
Replace the pump
61AllAir in the pumpRestricted CH flow due to air or a circuit restriction:
Check Flow and Return valves are open
Check for correct system pressure
Check the system is purged properly
62All
Full boiler calibration
required
This may occur when the PCB is replaced or if the parameters are altered in the air/gas section:
Carry out full calibration process as described
72All
Fast calibration
required
The PCB detects that some parameters have been altered
Carry out fast calibration process as described
73All
High flow NTC and
safety NTC difference
detected
The board detects an anomaly in the temperature readings difference between the flow NTC and safety NTC sensors
Faulty flow or safety NTC sensor
Check resistance reading on the sensors
Poor system circulation or blockage
74All
Safety flow sensor
anomaly
The PCB detects an anomaly on the safety NTC sensor:
Faulty safety NTC sensor
Check resistance reading on sensor
Replace the safety NTC sensor
77AllAn anomaly on the gas valve control is detectedAn anomaly on the gas valve control is detected
Check the electrode condition, replace if necessary
Check the inlet gas pressure is correct and carry out a full calibration process as described. If the fault persists replace gas valve
78AllAn anomaly on the gas valve control is detectedAn anomaly on the gas valve control is detected
Check the electrode condition, replace if necessary
Check the inlet gas pressure is correct and carry out a full calibration process as described. If the fault persists replace gas valve
79AllAn anomaly on the gas valve control is detectedAn anomaly on the gas valve control is detected
Check the electrode condition, replace if necessary
Check the inlet gas pressure is correct and carry out a full calibration process as described. If the fault persists replace gas valve
No lights onAlpha C23, C27 CB, CB50, CD50, CDC, CDR, CDS, CDX, HE, HECB, HESYElectricity faultCheck your electricity supply
Illuminated red A or BAlpha C23, C27 CB, CB50, CD50, CDC, CDR, CDS, CDX, HE, HECB, HESYBurner has failed to lightRotate selector switch to the reset position (3) and the ignition sequence will restart after a delay of about 30 seconds
Illuminated yellow B or CAlpha C23, C27 CB, CB50, CD50, CDC, CDR, CDS, CDX, HE, HECB, HESYBurner is alightNo action required
Flashing red A or BAlpha C23, C27 CB, CB50, CD50, CDC, CDR, CDS, CDX, HE, HECB, HESYOverheat thermostat has operated / Temperature sensor faultRotate selector switch to the reset position (3) to reset
Flashing yellow every five seconds or Illuminated Green DAlpha C23, C27 CB, CB50, CD50, CDC, CDR, CDS, CDX, HE, HECB, HESYElectrical supply to the boiler is onNo Action Required
Flashing yellow B or flashing Red AAlpha C23, C27, CB, CB50, CD50, CDC, CDR, CDS, CDX, HE,HECB, HESY,Temperature sensor faultContact a professional
Illuminated red A and flashing yellow B or Flashing red A and flashing red BAlpha C23, C27, CB, CB50, CD50, CDC, CDR, CDS, CDX, HE,HECB, HESY,Blocked flue or fan faultcontact a professional
Flashing yellow or flashing Red A or Flashing (alternating) red A and flashing (alternating) yellow BAlpha C23, C27, CB, CB50, CD50, CDS, CDX, HE,HECB, HESY,System pressure is very low and re-pressurisation is requiredContact a professional
Illuminated red A and flashing yellow BAlpha C27, CB, CB50, HE,HECBPump fault or restricted flowContact a professional
Flashing red A and Flashing red B and flashing yellow CAlpha CDRTemperature sensor wiring or flow and return connections incorrectContact a professional
Flashing red A and flashing red B and flashing yellow C indicatorsAlpha CDS, CDXFlue temperature too high (air in the heat exchanger, heat exchanger blockedContact a professional

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