Thermostat for 2 Stage gas furnace

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I recently had a Lennox G61 two-stage gas forced air furnace installed. The thermostat is a regular 1 stage programmable. The furnace has a jumper on the control board to work with a one stage or two stage thermostat.
My question is, am I better off to replace the thermostat with one for two stages of heating, or leave it the way it is? My thinking is that controlling the stages from the thermostat would be the way to go. I'm not sure how the furnace decides when to turn on stage two, but I believe it is simply based on time.
I'm thinking of putting in a Honeywell 8624D instead of the stat that is there now. Is this a good choice?
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WHY didn`t the installer cover this issue for you ???
WHY did you pay extra for 2 stage and not get a 2 stage stat ???
You are not telliing the whole story.
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Ok, I got 2 stage gas furnace but have just 1 stage thermostat. I decided not to upgrade my 1 stage thermostat as I did not see much of the benefit. From what I understand, this is how system works: Furnace is setup to work with one stage thermostat. It starts at lower output and works like that for 12 minutes. If thermostat still calls for heat, furnace switches to higher output. With 2 sttage thermostat - thermostat decides if to call for low output or high output. That is if lets say current temparature is 2 degrees from required temperature, thermostat right away will start furnace at higher output. So you are losing that lets say after setback it takes a bit longer to recover. But that is it. Is there any other advantages on having 2 stage thermostat?
Thanks

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I had no idea he put in a one stage stat.
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m Ransleysays...

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Is there 4 wire or 5 wire thermostat wire run from the furnace to the tstat location?

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It is 4 wire. I had already planned on having to change the wire if I upgrade the tstat and it appears it will be pretty easy to snake in the new wire.
On Mon, 8 Nov 2004 18:28:34 -0500, "HeatMan"

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For this type of furnace, I don't honestly see why you want to change the thermostat. The objective is to 'low fire' the furnace for the first 12 minutes. If that heats the residence sufficiently, then fine. Instead of firing high and using more gas, or overshooting the temperature. If the 'low fire' rate isn't getting the job done, the computer on the furnace switches to high after the 12 minute interval. So you only use the 'high' when necessary. Your using a 2 stage thermostat when the furnace manufacture provides you with a solution to use a 1 stage thermostat, and saves you from firing on the higher rate (more gas usage.) (I fully understand the 2 degree differential between 2nd stage and 1st stage.)
For my 2 cents, you have a newer 2-stage furnace is designed to work either with a 1-stage state, or 2 stage stat. It is more efficient only to use that amount of fuel that you need to keep your family comfortable. Using high fire when it's not necessary is like going as fast as you can from traffic light to traffic light, instead of just steadily getting there.
Are you seeing a need to switch to the 2 stage stat? Is the furnace getting the job done now? Is your family uncomfortable (too hot or too cold?)
--
Zyp
"J Kelly" < snipped-for-privacy@newsguy.com> wrote in message
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I wasn't sure how the furnace was supposed to work. The installer said the time delay was "about 5 minutes" which seemed way to short. Therefore, I wasn't sure if a different stat would work any better (or worse for that matter). On a further note, am I weird to want an installation manual for my furnace? I did not get one, but did have one for the furnace in my last house. I know I don't need it, but I like to know as much as possible about these types of things. Maybe it would explain in better detail how the two stages sequence.
I do plan to change the stat no matter what because I do not like the one that the furnace guy installed, it does not have separate programs for each day of the week, which for me is an important feature due to my non-standard work week. I also like to have the fan on all the time when I'm home, but on auto when I'm not home. That was my main reason for liking the 8624D.
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Zypher you are not correct, the second stage on my unit does not require a higher blower speed there by making 2nd stage more efficient. Remember Blowers take apx 360 watts . Or 35$ at .125Kwh 24x7. An AC blower will cons`ume the same Kwh at any Btu or CFM.
2 stage is for comfort...
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As long as you realize that you will need at least 5 conductor tstat wire for the 2 stage tstat....
The Honeywell VisionPro Tstat would be a good one for this application....

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On Tue, 9 Nov 2004 18:46:08 -0500, "HeatMan"

I knew about needing an extra wire, and already have a roll. I checked out the routing and it is a simple matter to fish the wire to the basement. I figure I can do it in 10 minutes or so.
Will give me something to do on my next day off, by then I should have the thermostat which I have already ordered.
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I think you are in the wrong NG. Experts like yourself should stay in HVAC

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Jealous that I know what I'm talking about?

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Naaaa, just giving you shit because I was stupid enough to ask a question in HVAC and got flamed.

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There's nothing I could do about that. You should have lurked for a while before you waltzed in....

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On Wed, 10 Nov 2004 07:25:33 -0500, "HeatMan"

I knew better than to ask over there.. I don't have a flame proof suit! ;-)

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One thing you forgot is your warranty, putting in a new stat is not beginner stuff, I would not do it unless I knew and checked all wiring and I don`t on 2 stage. You have 3 month old equipment, don`t risk damage or your warranty doing it yourself, you may be denied a warranty claim. Which leeds me to an earlier question, why even bother, you paid, it isn`t right. Unless you are the installer or got it used.
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This is Turtle.
Look A two stage thermostat is alway better on a two stage furnace. The next best thing is a single stag thermostat on a 2 stage furnace.
I would think it would work better and keep the air a even temp. in your home with the two stage thermostat than with the single stag thermostat.
TURTLE
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NEW furnace, NEW install , NEW Warranty and customer set up come to mind, or maybe THE TRUTH IS missing
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