| Error code | Possible fault | Installer action |
|---|---|---|
| FLASHED Green 1 TIME | Boiler temp reached | |
| 3 GREEN FLASHES | Temporary Flame Loss (No Reset Required) | Temporary error, self-reset. If it continues it goes to 3 red flashes (lockout). |
| 4 GREEN FLASHES | Communication Fault Between PCB And Control | Temporary error, self-reset. |
| 5 GREEN FLASHES | Parameter Error On PSU/PCB | Temporary error, self-reset. |
| 6 GREEN FLASHES | Miscellaneous Error | Temporary error, self-reset. |
| ONE RED FLASH | Sensor Error: Sensor Fault, Temperature Fault Or Flow Fault | Check wiring; sensors about 12 kΩ at 25 °C; sensor in the pocket; AAV open; system full and vented; pump running; flow/return orientation; blockages. |
| 2 RED FLASHES | Boiler Overheat Tripped | Vent the system; check water pressure; continuity across the overheat stat and APS if fitted; circulation direction, pump, valves; wiring; not air-locked. |
| 3 RED FLASHES | Ignition Fault. Boiler Has Failed To Light After 5 Attempts | Check wiring, supply pressure, purge air, spark, electrode condition, gas valve opening, condensate drain. |
| 4 RED FLASHES | Fan Fault | If the fan is not running, check power to the gas-air unit. If it is running, check APS (if fitted). Check the flue for blockages. |
| 5 RED FLASHES | Parameter Or PSU Error | Check PCB and loom; replace PSU and recommission; check wiring. |
| FLASHES RED 6 TIMES | Miscellaneous | Check wiring connections. If needed replace the PU and/or control/fan assembly. |
Gas work stays with a Gas Safe registered engineer. These steps are guidance from the manufacturer sequence, not a substitute for the handbook.