No C wire but possible work around

[ctleea]

Any issue with the Google Nest Thermostat if I use the green wire as a c wire?  I don't it will mean I cannot run the fan independently, but that's fine.  My current (no pun intended) thermostat has: Rc, G; W, and Y wire.

[Houptee · Accepted solution]

It should be ok and that is a recommended method to use G wire.

Just confirm the blower fan still comes on in both heat and ac without the g wire.

[Patrick_Caezza]

Do not use the G wire hack to create a C wire. This will cause your thermostat to lose the ability to control the fan independently. The best option is to use the Google Nest Power Connector.

[ctleea]

Well, I have never used a fan independently in 30 years.  Any other reason not to go with a G wire?

[Jenelyn_O]

Hi there,

Chiming in — if you don't use your fan wire to run your fan independently, you have two options. First, you will need to remove the old G-wire from your G-terminal and attach it to the C-terminal in both your thermostat and furnace. Second, we suggest using a Nest Power Connector as a substitute for C wire.

You can visit this link for more information.

I appreciate your help @Houptee and @Patrick_Caezza. 

Best,

Jenelyn

[Jenelyn_O]

Hi there,

I wanted to follow up and see if you still need help. Please let me know if you are still having any concerns or questions from here, as I would be happy to take a closer look and assist you further.

Best,

Jenelyn

[Jenelyn_O]

Hi there,

I'm just checking in to make sure that you've seen our response. Please let us know if you have any other questions or concerns as I will be locking this thread in 24 hours.

Best,

Jenelyn