Buderus error codes CO and 2f help

flyrod7

I have been getting error codes CO and 2f can someone help me repair my boiler GB142

EdTheHeaterMan

F2 appear to be a supply sensor and or safety sensor fault
CO appears to be a short circuit of a sensor or a incorrect or defective connection of the UBA Control (that is the brains of the system) with a sensor. The UBA is located at the lower left of the boiler under the cover. See item #2 in this illustration.


You can carefully remove this control after turning the screw in the middle of the control counter-clockwise. Inspect the pins to see if any of them are bent or mis-aligned. Carefully replace the UBA by lining up all the pins with the socket, then pressing gently on to the socket, then turning the center screw clockwise.

EdTheHeaterMan

You can check the connection of the supply sensor located on the pipe leaving the boiler at position 1 in this diagram.
The safety sensor is located on the left side near the center of the Cast Aluminum block as shown in this illustration.

those are the 3 things I would check to see if the wiring connection is proper. Sometimes just taking the plug apart and reconnecting the plug will refresh the connection. If that does not work then one of those 3 items are defective. the sensors are less expensive that the UBA. There is a way to test the sensors for accuracy with an accurate Ohm meter

flyrod7

Thank you Edward I will check this out again thanks for your advice.