Oil boiler with blue and white wirings only.

[Ffung]

Hi, my heating has two wires, white and blue. The nest plate does not show blue, so where do I place this wire? The old thermostat has a bridge connection from rc to rh. I understand, not needed with the nest thermostat. I have tried putting the blue to the R and still not able to start boiler. I have tested the voltage and the white carries about 34v consistent and the blue about 17v but with time it voltage drops. Help with understanding, what am I missing, thanks.

[Patrick_Caezza]

@Ffung 

What is the make and model of your boiler?

Can you post a picture of the original thermostat's wiring?

Can you post a picture of the thermostat wiring to the boiler?

[Ffung]

Hi, I am not sure how to up load pictures here, it is telling me files are too large. 

[Ffung]

@Patrick_Caezza 

Hi, I am not sure how to up load pictures here, it is telling me files are too large

[Ffung]

@Patrick_Caezza 

Let me attempt to describe the wiring in the boiler.

1) there is a transformer with a blue & white wires.

2) wires connects to three different valves. 

3) Blue wire from transformer then connects to a Blue and Red wire which I guess, gives power to the three separate valves.

4) The White wire is connected to this valve too

5 Then apart from the three wires Blue, Red and White. There is an additional Blue and White wires.

6) I believe these are the wires going to the thermostat.

7) Where the transformer Blue connects to the Red there is a White wire that goes to the boiler. The Blue to boiler is connected to the other blue that goes to the valves that turn when the boiler turns on.

I did the best I could to describe at this point. I think I need a red to go to the thermostat. Please let me know a solution, thank you.

[Ffung]

@Patrick_Caezza