Can I Wire the Single Zone Smart Thermostat for GE Appliances RV ACs with Just 2 Wires?

Updated 09/12/2025 | Published 08/24/2025

Question:

Single Zone Smart Thermostat for GE Appliances RV ACs - Black Part Number: GE89FR Can it be wired for 2 wire?

asked by: Bruce B

Expert Reply:

Hello Bruce,

I’m sorry, but you cannot hook up the Single Zone Smart Thermostat for GE Appliances RV ACs – Black # GE89FR with just two wires, and here’s why. This thermostat isn’t like a simple old-school furnace thermostat that only needs power and a call signal. Instead, it’s designed to work with GE’s RV air conditioner control boxes, and that setup requires three separate connections to function correctly.

The three wires it needs are: +12V power, 0V ground, and a communication signal (COMMS) line. The COMMS line is what allows the thermostat to actually “talk” to the control board inside your RV’s AC system. If you only ran two wires, say power and ground, the thermostat would light up, but it wouldn’t have any way to send or receive the commands needed to control cooling, heating, or fan speed. In short, it would power on, but it wouldn’t actually do anything.

What kind of camper is this going in? Any fun adventures this year? Where have you been, or where are you headed?

expert reply by: Kate F

Kate F.

9/12/2025

Hey Bruce, did you find a way to set up the thermostat with the three necessary connections? I'm curious because it could help others who might be trying to do the same thing with their RVs.