Two stage furnace

petehouk · 01-21-13, 12:05 PM

Hi everybody. I am considering a new thermostat, and I have a question about single- vs. two-stage furnaces.

I have a two-stage, forced air, gas fired furnace. I was looking for a new thermostat recently, and one that I was considering said that it was only compatible with single-stage furnaces. Until then, I didn't know that there was a difference between single- and two-stage thermostats.

So I looked at the installation instructions from my furnace, and it has a few different ways to wire up the thermostat; the one that my installer used was "two-stage heating with single-stage thermostat." There was also an option for "two-stage heating with two-stage thermostat."

Is there an advantage to using a two-stage thermostat in conjunction with a two-stage furnace? I paid extra for the two-stage feature. Am I getting the full advantage from it? Or will I get better performance with two-stage thermostat?

I am working on my basement now, and, among other improvements, I am tidying up the wiring before I paint the joists. If I need to replace the 4 conductor thermostat wire with a 5 conductor (which the two stage thermostat needs), then this would be the time to do it.

01-21-13, 12:05 PM	#1
petehouk Lurking Renovator Join Date: Dec 2012 Location: Ann Arbor, MI Posts: 13 Thanks: 0 Thanked 0 Times in 0 Posts	Two stage furnace Hi everybody. I am considering a new thermostat, and I have a question about single- vs. two-stage furnaces. I have a two-stage, forced air, gas fired furnace. I was looking for a new thermostat recently, and one that I was considering said that it was only compatible with single-stage furnaces. Until then, I didn't know that there was a difference between single- and two-stage thermostats. So I looked at the installation instructions from my furnace, and it has a few different ways to wire up the thermostat; the one that my installer used was "two-stage heating with single-stage thermostat." There was also an option for "two-stage heating with two-stage thermostat." Is there an advantage to using a two-stage thermostat in conjunction with a two-stage furnace? I paid extra for the two-stage feature. Am I getting the full advantage from it? Or will I get better performance with two-stage thermostat? I am working on my basement now, and, among other improvements, I am tidying up the wiring before I paint the joists. If I need to replace the 4 conductor thermostat wire with a 5 conductor (which the two stage thermostat needs), then this would be the time to do it.