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  • Alpha Boiler Fault Codes / Error Codes List

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    • Alpha Boiler Fault Codes / Error Codes List

    Updated: March 21, 2024

    An Alpha boiler is a budget boiler which is quite affordable. That is why they are prone to break downs more than more expensive boilers. However, Alpha boilers are highly rated on websites such as Trustpilot.

    Alpha Boiler Fault Codes

    An Alpha boiler is a budget boiler which is quite affordable. That is why they are prone to break downs more than more expensive boilers. However, Alpha boilers are highly rated on websites such as Trustpilot.

    You should keep in mind that it is not legal for you to remove the cover on your Alpha boiler and try to fix the problem yourself. A Gas Safe engineer should be contacted to fix any issue which you might be facing with your boiler or heating system. This page has the aim of providing you with a guide to help you diagnose the issue and have an idea about the problem and the cost. In some cases, fixing the problem might not worth the cost and getting a boiler replacement might be the answer.

    You can contact Alpha and they can come out and fix the problem if your boiler is in warranty. Other warranty conditions should be met too such as getting your boiler serviced annually and so on. Need a new Boiler? Get a quote in 30 seconds.

    Read Also : Main Boiler Error Codes / Fault Codes

    General Alpha Boiler Error/Fault Codes

    This table contains common Alpha boiler fault codes that apply to a range of Alpha boilers.

    Fault CodeFaultFault Description
    1alpha boiler ignition failureGas supply, pressure tubes, ignition electrode, flame sensor electrode, ignition generator, lead flame sensor, electrode lead, gas valve setting, gas valve printed circuit board (PCB)
    2Overheat boiler lockoutPump or flow problem, blocked heat exchanger, air in heat exchanger, overheat thermostat, thermal fuse (if open circuit then replace primary heat exchanger)
    3High flue thermostat temperatureBlocked or restricted primary flow, heat exchanger air flow blocked, flue restriction, flue sensor fault
    4Gas valve electrical connection faultGas valve lead connection fault, faulty gas valve or faulty printed circuit board (PCB)
    5Heating flow sensor faultFlow sensor wire connections, flow sensor faulty
    6Domestic how water (DHW) sensor faultDHW sensor wiring connection or DHW sensor faulty
    8Maximum number of resetsRefer to fault history codes
    10Primary system pressure lowCheck expansion vessel pressure (1 bar), leak in system, expansion relief valve operated or primary pressure switch
    12Cylinder sensor fault (FlowSmart only)Cylinder sensor wiring connections or cylinder sensor faulty
    15Internal wiring errorCheck internal wiring connections to printed circuit board (PCB), Combi boiler domestic hot water (DHW) sensor X4, System boiler link X14
    16Fan faultFan wiring connections, fan fault or printed circuit board (PCB) fault
    20Flame sensing faultCheck flame sensing electrode and lead printed circuit board (PCB) fault
    24Control panel button faultJammed control panel or printed circuit board (PCB) buttons
    25Overheat 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
    27Insufficient primary flowBlocked or restricted primary flow, air in heat exchanger, boiler or heating circuit valve closed, pump fault or primary flow sensor fault
    29Flue sensor faultSensor wiring connection or flue sensor faulty
    31Loss of communication with external control (Alpha Climatic)Remote control or receiver connection wiring
    37Low supply voltageCheck mains power supply
    38Loss of flame rectificationFlame sensing electrode and lead, check flue gas recirculation, check the gas valve settings and check the fan speed settings
    43Loss of flame rectificationCheck gas supply working, check flame sensing electrode and lead, check for flue gas recirculation, check the gas valve settings, check the fan speed settings
    44Safety lock outCheck external control (room thermostat) requests and rapid on/off hot tap requests
    46External sensor interventionExternal sensor and cable damaged or wet, continuity of external sensor and circuit, check connection at X19 on printed circuit board (PCB) and sensor connecting block
    47Reduced burner outputAir in heat exchanger, restricted primary flow, heat exchanger airflow blocked, flue restriction, flue sensor fault or pump fault
    51Climatic RF communication faultBatteries need replacing, distance between boiler and climatic control too great, interference object blocking signal (metallic)

    Read Also : Navien Boiler Error Codes / Fault Codes

    Alpha E-Tec, E-Tec Plus, Evoke Combi Boiler Error/Fault Codes

    Fault CodeFaultFault Description
    60Pump error (stuck or there is an electrical pump fault)Pump operation (may need to free the pump shaft), issue with pump wiring or pump replacement needed.
    61Air in the pump (restricted central heating flow)Flow and Return valves may not be open, iIncorrect system pressure, system not purged properly or flow return valves are open.
    70Return/flow sensor
    Exchange from possible wiring fault
    Issues with sensor wiring and connections.
    Issues with sensor resistance.
    75/76Return/flow sensor fault from possible failure of one or both sensorsIssues with sensor resistance.
    SRService reminderService reminder countdown has reached 0 (this will not stop boiler from working) – boiler needs servicing.

    Read Also : Sime Boiler Error Codes / Fault Codes | Smart Adapt

    Alpha E-TEC Regular Gas Boiler Error Codes

    Fault CodeFaultFault Description
    1Ignition failureCheck the gas supply, pressure tubes, ignition electrode, flame sensor electrode, ignition generator or lead flame sensor, gas valve setting and PCB.
    2Overheat boiler lockoutPump or flow problem. Caused by a blocked heat exchanger, air in heat exchanger, overheated thermostat, thermal fuse (if open circuit then replace primary heat exchanger).
    3High flue thermostat temperatureBlocked or restricted primary flow. Heat exchanger air flow blocked, flue restriction, flue sensor fault.
    4Gas valve electrical connection faultGas valve lead connection fault. Faulty gas valve or faulty PCB.
    5Heating flow sensor faultFlow sensor wire connections. Flow sensor faulty.
    6Internal wiring errorIncorrect wiring configuration detected. Internal wiring connections to PCB need checking.
    7Chimney sweep function is activeChimney sweep function is active. E07 is displayed on the climatic remote control.
    8Maximum number of resetsRefer to fault history codes
    12Cylinder sensor fault (FlowSmart only)Cylinder sensor wiring connection – cylinder sensor faulty.
    16Fan faultCheck fan wiring connection, fan fault or PCB fault.
    20Flame sensing faultCheck flame sensing electrode and lead PCB for faults.
    23Heating return sensor faultIncorrect return sensor resistance value – return sensor wire connections or sensor could be faulty.
    24Control panel button faultControl panel button is stuck in the ‘on’ position – check for jammed control panel buttons or jammed PCB button.
    27Insufficient primary flowBlocked or restricted primary flow. Air in heat exchanger, boiler or heating circuit valve closed, pump fault or primary flow sensor fault.
    29Flue sensor faultCheck sensor wiring connection – flue sensor faulty.
    31Loss of communication with external control (Alpha Climatic)Remote control or receiver connection wiring.
    37Low supply voltageCheck mains power supply.
    38Loss of flame rectificationCheck flame sensing electrode and lead and for flue gas recirculation. Check or adjust the gas valve settings. Check or adjust the fan speed settings.
    43Loss of flame rectificationCheck gas supply/working pressure, flame sensing electrode and lead, check for flue gas recirculation, check/adjust the gas valve settings, check/adjust the fan speed settings.
    44Safety lockoutCheck external control (room thermostat) requests. Rapid on/off hot tap requests.
    45High-temperature differenceThe boiler is detecting an unexpected increase between the system flow and return sensors. Boiler output is limited for boiler protection and once restored the boiler resumes regular operation.
    46Optional thermostat interventionNo continuity of optional thermostat circuit – check the optional thermostat and cable are not damaged or wet.
    47Reduced burner outputFlue thermostat has sensed high flue gas temperature and reduced the burner output to prevent damage. If the temperature continues to rise the boiler will lockout and the E03 error code will be displayed. This could be due to air in the heat exchanger, restricted primary flow or heat exchanger air blocked.
    49Return sensor high temperature interventionReturn sensor has detected a high temperature on the exchanger return circuit.
    51Climatic RF communication faultThe error between the communication of the climatic transmitter and boiler receiver. Could mean the batteries need replacing or the distance between the boiler and climatic control is too great or a metal object is blocking the signal.
    70Return flow sensor errorPossible wiring faults sensor is incorrectly fitted or the system is blocked – check the sensor wiring and connections, also check sensor resistance and circulation.
    71No primary temperature increase detectedFrom ignition the boiler detects no temperature rise in the primary circuit – check system filling and venting, airlocks preventing flow check, blocked flow, or closed valves.

    Read Also : Ferroli Boiler Error Codes / Fault Codes List

    Alpha Protec Plus System Error Codes

    Fault CodeFaultFault Description
    OA1Ignition failureIssue with gas supply.
    Ignition electrode position and spark issues.
    OA2Flame detection faultFlame sensing electrode connections.
    A short circuit to the electrode or wires.
    OA3Overheat thermostat lock-outFlame sensing electrode connections.
    A short circuit to the electrode or wires.
    OA5Fan speed faultProblem with flue /ventilation.
    Issue with air inlet manifold and pipe.
    Damage or fault with fan.
    Fan wire connections.
    OA7High flue temperature faultAir in the primary heat exchanger.
    System restrictions causing overheating.
    Flue run may have restrictions or blockages.
    OA8Flame circuit faultIncorrect gas supply.
    Ignition electrode position and spark.
    Issues with flame sensing electrode gap and connections.
    0A9Gas valve electrical errorValve connection issues.
    Main PCB.
    Gas valve operation issues.
    Gas contamination.
    OA15Flow and return sensor anomaly detected.
    (incorrect temperature value shown on sensor.)
    Poor or incorrect circulation.
    External circuit influences.
    Problem with resistances of flow and return sensors.
    OA16Flow sensor temperature rise incorrect (time taken for flow temperature to rise is too long.System circulation issues.
    System volume or flow is too high.
    Boiler output is insufficient for the system.
    OA17Return sensor temperature rise incorrect (time taken for flow temperature to rise is too long.System circulation issues.
    System volume or flow is too high.
    Boiler output is insufficient for the system.
    OA18Flow and return sensor anomaly detected. Sudden temperature change detected on the flow or return sensor.System circulation issues.
    Problem with operation of zone valves.
    Resistances and function of flow and return sensors needs checking.
    OA21Main PCB faultElectrical connections.
    Water ingress in connections.
    OA30Flow sensor short circuitFlow sensor connections and wires need checking.
    Water ingress in connections.
    OA31Flow sensor out of range. (sensor measures a temperature not in normal range.)Problem with flow sensor connections and damaged wires.
    Sensor resistance values wrong.
    0A37 – Pro Tec 50Insufficient system flow (if the system flow is too low for a certain length of time boiler will switch off)Flow switch reading needs checking.
    Restrictions or shut valves in system.
    Pump function issues.
    System pressure issues.
    OA43Return sensor short circuitProblem with return sensor connections and wires.
    Water ingress in connections
    OA44Return sensor out of range.
    Sensor measures a temperature outside normal working range
    Return sensor connections and damaged wires.
    Return sensor resistance values need checking.
    OA80Flow and return sensor connection fault (may occur after several minutes of boiler operation.)Wires are not connected to the correct sensors.
    OE2Flame sensing fault.Flame sensing electrode connections need checking.
    Short circuit to the electrode or wire.
    OE13Maximum number of resets reached. (Over 5 reset attempts have been reached within 15 minutes.)Investigate initial fault code displayed.
    Power supply needs to be turned Off/On to clear this code
    OE25Main PCB faultAll electrical connections need to be checked.
    Water ingress in connections.
    OE33Low power supply voltageElectrical socket connection issues.
    Problem with external power supply.
    Possible power disruptions
    OE34DHW sensor out of range (measures a temperature outside normal working range.)DHW sensor connections and damaged cables.
    Issues with DHW sensor resistance values
    OE37Insufficient system pressureSystem needs checking for circulation and restrictions.
    System pressure and gauge needs checking.
    Pressure switch and connections need checking.
    OE45Flue sensor short circuitFlue sensor connections and wires need checking.
    Water ingress in connections
    OE46Flue sensor out of range (measures a temperature outside of normal working range)Flue sensor connections, wires and flue sensor resistance values need checking.
    OE81Flow and return sensor anomaly detected (the sensor shows an incorrect temperature value)Poor or incorrect circulation / external circuit influences resistance of flow return sensors need checking
    OE98Flow and return sensor anomaly detected (sensor shows incorrect temperature value)M to O Connections need checking
    Compatible software on PCB needs checking
    OE99Simple cascade communication errorWiring connections needs checking on all boilers.
    Configuration, parameter 38.
    FE94Display PCB fault.Electrical connections to display board need checking.
    Water ingress in connections.
    Damage to buttons or LCD screen.
    FE95External flow sensor out of range or short circuit/
    External flow sensor measures a temperature outside of normal working
    range.
    External flow sensor connections and wires need checking for damage. External flow sensor resistance values need checking to make sure they are between 5 and 0
    FE96External sensor faultExternal sensor connections and wires need checking.
    Water ingress in connections.
    Boiler parameter settings are incorrect.
    FE97Boiler PCB configuration error (may occur if the main PCB or display PCB is changed.)All electrical connections.
    Incorrect parameter settings on PCB.
    Press ‘-‘ CH button until ‘AUTO’ appears, then press and
    hold ‘RESET’ button until ‘bu1’ appears

    Read Also : ATAG Boiler Error Codes / Fault Codes

    Alpha Flashing Light Error Codes

    Light SequenceFaultFault Description
    No lights onElectricity faultCheck your electricity supply
    Illuminated red A or BBurner 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 CBurner is alightNo action required
    Flashing yellow every 5 seconds or illuminated green DElectrical supply to the boiler is onNo action required
    Flashing yellow B or flashing Red ATemperature sensor faultContact a Gas Safe engineer
    Illuminated red A and flashing yellow B or Flashing red A and flashing red BBlocked flue or fan faultContact a Gas Safe engineer
    Flashing yellow or flashing Red A or Flashing (alternating) red A and flashing (alternating) yellow BSystem pressure is very low and re-pressurisation is requiredContact a Gas Safe engineer
    Illuminated red A and flashing yellow BPump fault or restricted flowContact a Gas Safe engineer
    Flashing red A and Flashing red B and flashing yellow CTemperature sensor wiring or flow and return connections incorrectContact a Gas Safe engineer
    Flashing red A and flashing red B and flashing yellow C indicatorsFlue temperature too high (air in the heat exchanger, heat exchanger blockedContact a Gas Safe engineer

    What is the error code E on the alpha boiler?

    Error codes beginning with “E” typically indicate a fault or issue with the boiler. Common causes could include problems with the pressure, ignition, or other internal components. Consult your boiler’s manual or contact the manufacturer’s customer support for specific information on the “E” error code for your Alpha boiler.

    Why is my alpha boiler flashing A and B?

    A and B may represent specific fault codes or stages in the diagnostic process. Check your boiler’s manual for the meanings of these codes or contact the manufacturer’s customer support for assistance.

    What are boiler fault codes?

    Boiler fault codes are alphanumeric codes displayed by the boiler to indicate specific issues or malfunctions. These codes help technicians diagnose and repair problems efficiently. Refer to your boiler’s manual for a list of fault codes and their meanings.

    What does D mean on Alpha boiler?

    Again, the meaning of fault codes can vary between models. “D” could indicate a specific issue, such as a problem with the diverter valve or another internal component. Refer to your boiler’s manual for accurate information on the “D” fault code.

    What is E and C in boiler?

    Similar to the “E” and “D” codes, the meaning of “E” and “C” codes can vary. Commonly, “E” codes signify electrical faults, while “C” codes might relate to issues with the combustion process or other components. Check your boiler’s manual for precise details.

    How do I fix the E error on my boiler?

    To address an “E” error on your boiler, you can try the following general steps:
    Check the boiler’s pressure to ensure it’s within the recommended range.
    Reset the boiler according to the manufacturer’s instructions.
    Verify that the gas supply is sufficient and the pilot light is lit.
    If the issue persists, contact a qualified heating engineer or the boiler manufacturer’s support for professional assistance.