2 wire hookup red wire and white . my old thermostat RC & RH and jumpered together.

[Coddingsrc]

Can i connect to the Rc or the Rh on the nest thermostat

[Houptee]

No you never use jumpers on the Nest or any smart thermostat.

Put red in Rh only.

If you can its best to use a C wire if you have a extra wire in the cable or if you can pull a new 5 conductor cable up the wall from the heating system it is more reliable power to the nest.

You would need to connect the C wire to the C common terminal on the heater also.

It might be ok without the C wire but if battery keeps draining then you need to add a C wire.

[aatienza]

Hey Coddingsrc,

Checking in — we hope you've got the answer you're looking for. Let us know if you have more questions in mind.
 

I appreciate the help, Houptee.

Thanks,

Archie

[aatienza]

Hey there,

I just wanted to follow up to see if you still need our help. Please let us know as we would be happy to answer any questions you may have. 
 

Thanks,

Archie

[aatienza]

Hello there,

Just checking in to make sure that you've seen our responses. Please let me know if you have other questions or concerns as I will be locking this in 24 hours if I won't hear back from you again. Feel free to start a new thread and we'll be happy to help.
 

Thanks,
Archie