| Atag Boilers Fault Code | Possible Cause |
|---|---|
| 10 | Outside sensor error |
| 20 | Flow sensor error |
| 40 | Return sensor error |
| 50 | DHW sensor error (iC-Range only) |
| 61 | Bus communication error |
| 78 | Water pressure out of range |
| 101 | Overheat error |
| 105 | Venting program active when power turned on or interrupted (runs approx. 7 mins) |
| 108 | Pressure needs filling to < 0.5 bar |
| 109 | Pressure > pmax error |
| IP4 | Pressure needs filling to 0.5 – 0.8 bar |
| 110 | Safety temperature exceeded / Send probe damaged |
| 111 | Maximum pressure exceeded |
| 112 | Return probe error – could be damaged |
| 114 | Outdoor sensor error – could be damaged |
| 117 | Pressure too high (> 3 bar) or pump pressure increase too high (iC & iS Range only) |
| 118 | Pressure too low (< 1 bar) or pump pressure increase too low) no pump detection) (iC & iS Range only) |
| 119 | Link on X2 position 4 and 5 missing |
| 129 | Fan error (fan does not start up) |
| 133** | No flame after 5 ignition attempts |
| 141 | Central heating flow switch is open |
| 151 | Fan error (speed control is not achieved or is out of range) or control unit defective |
| 154 | Flow temperature increases to fast, return > flow |
| 201 | Domestic hot water (DHW) probe damaged |
| 203 | Tank probe damaged |
| 303 | Printed circuit board (PCB) error |
| 304 | Too many resets have occured |
| 501 | No flame detected |
| 612 | Fan fault – fan isn’t starting up |
Other Fault Codes
If you see a spanner symbol this means either; 1. Your boiler is in service mode. 2. It could be blocking. If the boiler is blocking the code it’s only temporary and will clear itself or will lock the boiler after several attempts if the error keeps on occurring.
** ATAG Error code 133
If you are seeing the error code 133, your boilers flame is failing after 5 ignition attempts. This could be down to your condensate drain pipe freezing. A frozen condensate pipe is something that is often easily fixed
See Also ATAG Boiler Manuals for specific PDF files
