Where to connect Outdoor sensor on WM CGa4 PIDN Series 3 boiler

mariusz6100 · November 27

Hello, I am having difficulty finding information on how to connect the Outdoor Temperature Sensor Kit, 381-356-586 to CGa4-PIDN series 3 boiler control unit. There is no drect plug in where I can connect the harness provided with the kit and there are no instructions how to connect it. I have not found any information whether an outdoor reset kit is also reuqired. From what I could find, it would seem I should be able to connect the sensor to the contiol unit directly.

The control unit has ODT terminal for 1 wire which seems to be outdoor temperature sensor at C9-1 (same as P9-1 on the other wiring diagram), but I have no idea where I should plug in the second wire and whether C9-2 24VAC Common is the right spot (same as P9-2 on the other wiring diagram). Or I may be misreading the diagram all together.

Any heklp is apreciated and I am including pics of the diagram and control board.

Here is the manual diagram, there is no connection to the harness on the control board:

Here is the diagram from the boiler

And here is the pic of the control unit

EBEBRATT-Ed · November 27

I am guessing.

I think you connect to the orange plug at the top left corner of the control. But it looks like you already have a wire connected to the ODT terminal a red wire. I would guess the other ODT wire would connect to the common.

I will check further. Where does that red wire go now?

hot_rod · November 27

It sure looks like the two right side terminals 1 &2, on the orange block?

mariusz6100 · November 27

Yes I think the orange block 1 and 2 (C9-1 and C9-2) right now, the sensor is connected to 1 (red wire) and 4 (white wire) so moving the white wire from 4 to 2.