cancel
Showing results for 
Search instead for 
Did you mean: 

2 wire connection for nest thermostat -E294

bmwaterman
Community Member

I have a basic 2 wire, 24 volt furnace thermostat cilrcuit.  Which terminals do I connect the wires to on a Nest Thermostat.  I presentoy have an E 294 error with the wires connected to  "W" & "R".

1 ACCEPTED SOLUTION

MelbaDT
Community Specialist
Community Specialist

Hey bmwaterman, 

 

Checking back in — still need our help?

 

Best, 

Melba

View solution in original post

4 REPLIES 4

Patrick_Caezza
Gold Product Expert
Gold Product Expert

It sounds like you have a system that is expecting just a switch closer to the R and W terminals.

The Google Nest Thermostat 

  • Requires the Nest Power Connector or a common ("C") wire. Based on your system and wiring setup or your use of a zone controller, you’ll need the Nest Power Connector or a C wire to use this thermostat. Be sure to add a Nest Power Connector to your cart. See g.co/nest/cwire for details.

You probably will also need an external 24Vac transformer if there is no C wire on the furnace.

 

This is how you can wire it without a C wire

 

2022-04-06_182952.jpg

2022-03-01_173137.jpg

MelbaDT
Community Specialist
Community Specialist

Hey folks, 

 

Thanks for your answer and for providing the wiring diagram, Patrick_Caezza. 

 

bmwaterman, I'm jumping in to ensure everything is covered here. I also recommend that you check on the suggested troubleshooting guide here: https://bit.ly/3FtQbnk

 

Best, 

Melba

MelbaDT
Community Specialist
Community Specialist

Hey bmwaterman, 

 

Checking back in — still need our help?

 

Best, 

Melba

MelbaDT
Community Specialist
Community Specialist

Hi, 

 

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