- Alpha Boiler Error Codes
Alpha Boiler Error Codes
Listed below are Alpha boiler fault codes and Alpha boiler Manuals.
Fault Code
|
Models Affected
|
Fault
|
Possible Cause |
---|---|---|---|
1
|
All | Ignition failure | Gas 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 |
2
|
All | Overheat boiler lock out | Pump or flow problem Blocked heat exchanger Air in heat exchanger Overheat thermostat Thermal fuse (if open circuit then replace primary heat exchanger) |
3
|
All | High flue thermostat temperature | Blocked or restricted primary flow Heat exchanger air flow blocked Flue restriction Flue sensor fault |
4
|
All | Gas valve electrical connection fault | Gas valve lead connection fault Faulty gas valve Faulty PCB |
5
|
All | Heating flow sensor fault | Flow sensor wire connections Flow sensor faulty |
6
|
All | DHW sensor fault | DHW sensor wiring connection DHW sensor faulty |
8
|
All | Maximum number of resets | Refer to fault history codes (INFO menu d9) |
10
|
All | Primary system pressure low | Check expansion vessel pressure (1 bar) Leak in system Expansion relief valve operated Primary pressure switch |
12
|
All | “Cylinder sensor fault (FlowSmart only)” | Cylinder sensor wiring connections Cylinder sensor faulty |
15
|
All | Internal wiring error | Check internal wiring connections to PCB Combination boiler DHW sensor X4 System boiler link X14 Refer to wiring diagram |
16
|
All | Fan fault | Check fan wiring connections Fan fault PCB fault |
20
|
All | Flame sensing fault | Check flame sensing electrode and lead PCB fault |
24
|
All | Control panel button fault | Check for jammed control panel buttons Check for jammed PCB buttons |
25
|
All | Overheat lock out | Air 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 |
27
|
All | Insufficient primary flow | Blocked or restricted primary flow Air in heat exchanger Boiler or heating circuit valve closed Pump fault Primary flow sensor fault |
29
|
All | Flue sensor fault | Check sensor wiring connection Flue sensor faulty |
31
|
All | Loss of communication with external Control (Alpha Climatic) | Remote control or receiver connection wiring Remote control or receiver |
37
|
All | Low supply voltage | Check mains power supply |
38
|
All | Loss of flame rectification | Check flame sensing electrode and lead Check for flue gas recirculation Check/adjust the gas valve settings Check/adjust the fan speed settings |
43
|
All | Loss of flame rectification | Check 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 |
44
|
All | Safety lock out | Check external control (room thermostat) requests Rapid on/off hot tap requests |
46
|
All | External sensor intervention | Check 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 |
47
|
All | Reduced burner output | Air in heat exchanger Restricted primary flow Heat exchanger air flow blocked Flue restriction Flue sensor fault Pump fault |
51
|
All | Climatic RF communication fault | Batteries require replacing Distance between boiler and climatic control too great Interference Object blocking signal (metallic) |
No lights on
|
Alpha C23, C27 CB, CB50, CD50, CDC, CDR, CDS, CDX, HE, HECB, HESY | Electricity fault | Check your electricity supply |
Illuminated red A or B
|
Alpha C23, C27 CB, CB50, CD50, CDC, CDR, CDS, CDX, HE, HECB, HESY | Burner has failed to light | Rotate selector switch to the reset position (3) and the ignition sequence will restart after a delay of about 30 seconds |
Illuminated yellow B or C
|
Alpha C23, C27 CB, CB50, CD50, CDC, CDR, CDS, CDX, HE, HECB, HESY | Burner is alight | No action required |
Flashing red A or B
|
Alpha C23, C27 CB, CB50, CD50, CDC, CDR, CDS, CDX, HE, HECB, HESY | Overheat thermostat has operated / Temperature sensor fault | Rotate selector switch to the reset position (3) to reset |
Flashing yellow every five seconds or Illuminated Green D
|
Alpha C23, C27 CB, CB50, CD50, CDC, CDR, CDS, CDX, HE, HECB, HESY | Electrical supply to the boiler is on | No Action Required |
Flashing yellow B or flashing Red A
|
Alpha C23, C27, CB, CB50, CD50, CDC, CDR, CDS, CDX, HE,HECB, HESY, | Temperature sensor fault | Contact a professional |
Illuminated red A and flashing yellow B or Flashing red A and flashing red B
|
Alpha C23, C27, CB, CB50, CD50, CDC, CDR, CDS, CDX, HE,HECB, HESY, | Blocked flue or fan fault | Contact a professional |
Flashing yellow or flashing Red A or Flashing (alternating) red A and flashing (alternating) yellow B
|
Alpha C23, C27, CB, CB50, CD50, CDS, CDX, HE,HECB, HESY, | System pressure is very low and re-pressurisation is required | Contact a professional |
Illuminated red A and flashing yellow B
|
Alpha C27, CB, CB50, HE,HECB | Pump fault or restricted flow | Contact a professional |
Flashing red A and Flashing red B and flashing yellow C
|
Alpha CDR | Temperature sensor wiring or flow and return connections incorrect | Contact a professional |
Flashing red A and flashing red B and flashing yellow C indicators
|
Alpha CDS, CDX | Flue temperature too high (air in the heat exchanger, heat exchanger blocked | Contact a professional |
- To get your Alpha Boiler Repaired, call us today on Cardiff 02920 140240
- Call for a Boiler repair today on Cardiff 02920 140240
Call for a Boiler repair today on Cardiff 02920 140240

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