Thermostat! Can this be done?

[RodneyG]

Hey everyone, i have a split system air and electric furnace with a 2 wire thermostat. I would like to be able to use only 1 thermostat to be able to control my OWB, air, and my electric furnace as back up so the electric furnace will come on if in case something happens and the OWB can't make the temp. Like if i may be away from home for a few days. Can i use a 2-stage heat and a 1 stage air like the honeywell RTH7500D for this kind of hook-up? http://www.honeywellcentral.com/product/0-85267-25724-4.html I realize that i will have to run new thermostat wire or will i have to use 2 seperate thermostats? Any ideals on this set-up or any suggestions?


THANKS, Rodney

 

[PA Plumber]

1st - OWB
2nd - "Electric Furnace" is that a heat pump?

 

[RodneyG]

It's just a plain ol electric furnace. Everything will share the same blower OWB, A/C, and the Electric furnace.

THANKS, Rodney

 

[ckr74]

That Honeywell is a good thermostat, but I would probably go with a stat that you can adjust upstage on. Totaline or Robertshaw makes that type and you can also adjust time before second stage kicks in. The Honeywell will have amind of it's own and no adjustment as far as when second stage or electric furnace takes over. You might want to go to mfg's websites and do some research first so you can get an idea on how they work. Hope this helps.

 

[iCreek]

I was going to use a 2 stage thermostat when I installed my OWB, but was told you can't have much difference between the stages, like 2 - 4 degrees max. Maybe an HVAC person can jump in and correct me if that is wrong. So we installed an additional White Rodgers and set them at different temps, Wood heat at 74 and Propane at 65... Of course the propane never kicked on last winter...

Of course I had to run another wire to the new stat and the propane furnace and install a relay, I had already run a thermostat wire to the OWB.

 

[mistergreentree]

I'm just now getting my OWB, but I also went with double stats. The way I was told to do it was to hook into my original gas thermostat's blower control wires and run those to the new thermostat. What I plan on doing is setting the gas furnace thermostat low and the OWB thermostat higher. When the OWB stat calls for heat it will turn on the blower and if I am gone and need the gas to kick on it is still hooked in as originally done.

 

[abohac]

Hey everyone, i have a split system air and electric furnace with a 2 wire thermostat. I would like to be able to use only 1 thermostat to be able to control my OWB, air, and my electric furnace as back up so the electric furnace will come on if in case something happens and the OWB can't make the temp. Like if i may be away from home for a few days. Can i use a 2-stage heat and a 1 stage air like the honeywell RTH7500D for this kind of hook-up? http://www.honeywellcentral.com/product/0-85267-25724-4.html I realize that i will have to run new thermostat wire or will i have to use 2 seperate thermostats? Any ideals on this set-up or any suggestions?


THANKS, Rodney

I'd go with a dedicated therm for the OWB. I did have to have amy furnace man from Lennox do some wire switching for me on the furnace so each therm controlled the blower but reg therm also told the furnace to ignite incase OWB went out.

 

[RodneyG]

That Honeywell is a good thermostat, but I would probably go with a stat that you can adjust upstage on. Totaline or Robertshaw makes that type and you can also adjust time before second stage kicks in. The Honeywell will have amind of it's own and no adjustment as far as when second stage or electric furnace takes over. You might want to go to mfg's websites and do some research first so you can get an idea on how they work. Hope this helps.

Thanks everyone for the info.
ckr74 would you happen to know a model # for the Totaline or Robertshaw that i would be able to use for what i'm wanting to do?


THANKS, Rodney

 

[ckr74]

Robertshaw 9820i2 or Totaline 374-1800. I really like the other suggestions of using an additional thermostat. Like said previously you need more of a differential for that kind of back-up heat.