Nest Power Connector Problem

[RobertNorth]

I installed the nest thermostat on a 2 wire system and had the N260 error message.  I then installed the nest power connector to solve the error message now I am receiving the N261 error message.  I checked the voltages and have 25vac on the input to the power connector and 25 vac between the C and R wires but nothing between the R and  W wires and nothing between the C and W .  The thermostat does not detect the W wire .  I don’t know and cannot find what I should measure between the R and W or the C and W wires.  Can anyone please help.

[Patrick_Caezza]

What type of 2-wire system are you trying to set up?

[RobertNorth]

It is an oil fired hot water baseboard with a Honeywell controller on the NTI boiler 

[Patrick_Caezza]

Good chance you will need to add an external 24VAC transformer.

Here is an example of what I am talking about.

 

[RobertNorth]

Thank you for your help.  I gave up on the thermostat and returned it.  I will look for one that will work without the ancillary equipment that the nest requires.  

[MelbaDT]

Hey folks, 

Thanks for providing the diagram and for answering, Patrick_Caezza. 

RobertNorth, sorry that you had to go through this and we're sad to see you go. Should you be willing to give us a chance again in the future, you know where to find us. 

Best, 

Melba

[MelbaDT]

Hey there, 

I haven't heard from you in a while so I'll be locking this thread if there is no update within the day. If you have any new issues, updates or just a discussion topic, feel free to start a new thread in the community.

Best, 

Melba

[RobertNorth]

Do you have a nest power connector unit if so could you please measure the voltages between all  wires of the output and let me know what you measure