ATAG Boiler Error Codes

ATAG Boiler Error Codes

ATAG Boiler Error Codes

Error Symbol

When your ATAG boiler has an error, you will see an error symbol like the one on the right. This symbol is normally accompanied by one of the codes in the tables below.

Fault Code System Behaviour
10 Outside sensor error
20 Flow sensor error
40 Return sensor error
61 Bus communication error
78 Water pressure out of range
105 Venting program active when power turned on / interrupted (runs for 7 mins)
110 Exceeded safety temperature
111 Exceeded maximum pressure
119 X2 link position 4 and 5 missing
129 Fan doesn’t start
133 No flame after 5 ignition attempts
151 Fan error or control unit defective (speed control is not achieved)
154 Return greater than flow – flow temperature increases too fast
101 Overheat error
102 Pressure sensor fault
104 Flow check failed
108 Pressure needs filling to < 0.5 bar
1P4 Pressure needs filling to 0.5 – 0.8 bar
109 Pressure > Pmax error
110 Send probe damaged
112 Return probe error – could be damanged
114 Outdoor sensor error – could be damaged
141 Central heating flow switch is open
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

IC & IS Combi Boiler Error Codes

Fault Code System Behaviour
50 Domestic hot water (DHW) sensor error
117 Pressure greater than 3 bar or pump pressure increase is too high
118 Pressure less than 1 bar or pump pressure increase too low (no pump detection).

Other Fault Codes

Spanner Symbol

If you see a spanner symbol this could be one of two things; firstly it could mean your boiler is in service mode. Secondly it could be blocking, if the boiler is blocking the code is 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, you can find out how in this guide to defrosting a condensate pipe.

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