Alpha Boiler Fault Code & Common Errors
Has a fault developed on your Alpha Boiler? This reliable boiler model can still on occasions have issues and may produce an error code to let you know what is wrong with it.
We have compiled a list of all the Alpha boiler error codes so you are aware of the fault and can get some more detail about what it means. If you are unable to fix the issue, or require help from a professional we are able to put your details forward to a professional service & repair team which can help you on your way to a warm home.
List of Alpha Numeric Boiler Faults & Errors
If your Alpha boiler is playing up then it may be displaying an error code, if this is a numeric code then you can find in our table below:
| Fault Code | Potential Cause | Fault |
|---|---|---|
| 1 | 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 Printed Circuit Board | Failed ignition |
| 2 | Blocked heat exchanger Pump or flow issue Air in heat exchanger Overheat thermostat Thermal fuse | Boiler locked out after overheating |
| 3 | Heat exchanger air flow blocked Flue sensor fault Flue restriction Blocked or restricted primary flow | High flue thermostat temperature |
| 4 | Faulty gas valve lead connection Faulty gas valve Faulty printed circuit board (PCB) | Electrical connection fault on gas valve |
| 5 | Flow sensor faulty Flow sensor wire connections | Heating flow sensor fault |
| 6 | DHW sensor wiring connection or sensor faulty | DHW sensor fault |
| 8 | Info menu D9 - Refer to fault code history | Maximum number of resets |
| 10 | Expansion relief valve operated Primary pressure switch Check expansion vessel pressure | System pressure low |
| 12 | Cylinder sensor faulty Cylinder sensor wiring connections | Only on the FlowSmart - Cylinder sensor fault |
| 15 | Interal wiring connections to PCB Combi boiler DHW sensor | Wiring error internally |
| 16 | Fan fault printed circuit board (PCB) Check fan wiring connections | Issue with the fan |
| 20 | Check flame sensing electrode and lead PCB fault | Flame sensing fault |
| 24 | Check for jammed printed circuit board (PCB) buttons Check for jammed control panel buttons | Button fault on the control panel |
| 25 | 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 | Lock out due to overheating |
| 27 | Blocked or restricted air flow Air in heat exchanger Boiler or heating circuit valve closed Pump fault Primary flow sensor fault | Insufficient primary flow |
| 29 | Check sensor wiring connection Faulty flue sensor | Fault with flue sensor |
| 31 | Remote control or receiver / wiring | Loss of communication with Alpha Climatic |
| 37 | Check mains power supply | Supply voltage low |
| 38 | Check flame sensing electrode and lead Check for flue gas re circulation Check/adjust the gas valve settings Check/adjust the fan speed settings | Loss of flame rectification |
| 43 | Check gas supply / working pressure Check flame sensing electrode and lead Check for flue gas recirculation Check/adjust the gas valve settings Check/ adjust fan speed | Loss of flame rectification |
| 44 | Check external control requests Rapid on/off hot tap requests | Lock out for safety |
| 46 | Check there is no damage or wet to the external sensor Check continuity of external sensor and circuit Check connection at X19 on PCB and sensor connecting block | External sensor intervention |
| 47 | Heat exchanger air flow blocked Flue restrictions Flue sensor fault Pump fault Air in heat exchanger | Reduced burner output |
| 51 | Batteries require replacing Boiler and climatic control distance too great Object blocking signal | Communication fault with Climatic RF |
List of Alpha Letter Flashing or Illumination Boiler Faults & Errors
In this section you can find a list of all the errors which involve lights flashing or illuminating:
| Fault Code | Potential Cause | Fault | Model(s) Affected |
|---|---|---|---|
| No lights on | Check your electrical supply | Electricity fault | HE, HESY, HECB, CDX, CDS, CDR, CDC, CD50, CB50, CB, C27, C23 |
| A or B illuminated red | Turn selector switch to the reset position and the ignition sequence will restart, which takes about 30 seconds | The burner has failed to light | HE, HESY, HECB, CDX, CDS, CDR, CDC, CD50, CB50, CB, C27, C23 |
| B or C illuminated yellow | N/A | Burner is alight | HE, HESY, HECB, CDX, CDS, CDR, CDC, CD50, CB50, CB, C27, C23 |
| A or B flashing red | Turn selector switch to reset position | Temperature sensor fault / overheat thermostat has operated | HE, HESY, HECB, CDX, CDS, CDR, CDC, CD50, CB50, CB, C27, C23 |
| Every five seconds flashing yellow or illuminated green D | N/A | Electrical supply to the boiler is on | HE, HESY, HECB, CDX, CDS, CDR, CDC, CD50, CB50, CB, C27, C23 |
| B flashing yellow or A flashing red | Fill in our contact form for professional advise | Temperature sensor fault | HE, HESY, HECB, CDX, CDS, CDR, CDC, CD50, CB50, CB, C27, C23 |
| A illuminated red and B flashing yellow or A flashing red and B flashing red | Fill in our contact form for professional advise | Fan fault or blocked flue | HESY, HECB, HE, CDX, CDS, CD50, CB50, CB, C27, C23 |
| Flashing yellow or flashing Red A or Flashing (alternating) red A and flashing (alternating) yellow B | Fill in our contact form for professional advise | Very low system pressure, re pressurisation required | HESY, HECB, HE, CDX, CDS, CD50, CB50, CB, C27, C23 |
| A illuminating red and B flashing yellow | Fill in our contact form for professional advise | Restricted flow or pump fault | HECB, HE, CB50, CB, C27 |
| A & B flashing red and C flashing yellow | Fill in our contact form for professional advise | Temperature sensor wiring or flow and return connections incorrect | CDR |
| A & B flashing red and C flashing yellow | Fill in our contact form for professional advise | The temperature of flue is too high | CDX, CDS |