Navien NHB Condensing Boiler and Nest Thermostat

[Kimosabe3]

Hello - I would like to install the Nest Thermostat (not E nor Learning) to control the boiler. the old thermostat used 2 wire (R & W), which are connected to CN10 on the NHB board. I have added a blue and green wire to provide power to the thermostat but don't know which terminals these wires should go.
My research indicates AC 24V will be the two terminals on CN25. I believe the left CN25 terminal is common so blue wire here and then the C terminal on the Nest. I think the right CN25 terminal is hot or grounding? so a green wire would go here? but the G terminal on the Nest is for fans? where should this wire go?
attached are pictures and would appreciate the advice.

[Jake]

Hey Kimosabe3,

Sorry for the late response. I wanted to follow up and ensure you are good to go. Please let me know if you still have questions about the wiring of your device, as I would be happy to take a closer look and assist you further. 

Best regards,
Jake

[Jake]

Hey Kimosabe3,

I want to ensure you are good to go, and everything is working properly. Please let me know if you are still having trouble, as I will be locking the thread in 24 hours due to inactivity. 

Best regards,
Jake

[Jake]

Hey Kimosabe3,

It has been a few days since the last reply, and I am going to lock the thread at this time. If you have any questions, please feel free to create a new post. 

Best regards,
Jake