[jmarro]

Hi Folks- first time post. Hope its not too long. I recently completed construction of my personal home here in Minnesota. My choice for the furnace was as noted in the title here. It is 92.9 efficient modulating furnace with a Rodgers 1F95-1282 Programmable MultiStage t-stat. I paid someone to fabricate the plenum and set the furnace and I did rest. HVAC is not my forte and as such I think there might be some fine tuning needed on this. the fabricator sized the system and instructed me on trunk sizes etc. Its a clean install. I paid the fabricators service guy to adjust the air to air for me and also start it up. At that time it was cooling season. Well, when I started heating the A/C would trigger along with the heat. Not very efficient eh. So I went to the t-stat with the manual and four pages of programming and realized that it was programmed for a heat pump. I changed that and that fixed that. My concern now is the dip switches for the airflow. Rather than go through the whole deal, is there someone versed in this that can tell me how I should be setting the airflow switches? I am unsure which mode I should be operating in-single stage modulating or two stage? In two stage, first stage 40% of capacity always and then 2nd stage, phase one zero to five minutes 65%/2nd stage phase two after five minutes 100% ? Or should I be operating in single stage modulating? Lots of other settings depending on rise rates and that, but basically- where is a good start in your terms to set this thing. Just seems like with the extreme insulating I did, (closed cell) that it is costing too much to heat. My first guess is that the fan speed is not great enough, even keeping it on all the time as the air to air exchanger instructions suggest, there still seems to be a problem getting heat to the farther runs.

I want to add that i have a great appreciation for your trade. i did this myself with verbal guidance from the fabricator, (older guy that has been doing it for ages and I think the technology has gotten away from him) and it was tough work. I learned some tricks along the way with his input, but honestly, I will never hang trunks like that alone again! Lastly- the system has three zones with manual dampers and I have played around with those as well as the dampers ahead of the registers at every run.

Thanks in advance- Joe

 

[crmont]

You cannot use the modulating function with that thermostat. (I think you should scrap the white rogers and get the rheem/ruud mod stat.) No matter what you do, follow the book. It has very specific instructions on how to set the cfm at the 40, 65 and 100 percent firing rates. The factory settings are usually close. If you have duct issues it is important to record the temperature rise and adjust accordingly. No furnace setting is going to fix that cold zone. That is simply a duct balancing issue.

BTW It's either single stage OR modulating with the factory dip settings. You see, the control board has a V terminal. This is the modulating input terminal. The board automatically goes into the mod function when it gets a signal on V. The V signal is whats called a pulse width modulating input. It must be used with the "V" terminal on the rheem/ruud mod stat. The first gen of this stat was kind of a POS but now it's a modified honeywell vision pro and it's quite nice.

Side note. I think the choice of the "v" idenification was poor because there are stats out there with a v/vr idenification used by older lennox stuff.

 

[jmarro]

Thanks for the response. I am a bit confused- the t-stat is actually a rudd(has a rudd sticker over the rogers one on the backplate.) This is a link to the IF95-1277 I cannot find anything on the IF95-1282 http://www.ntsupply.com/files/products/1f95-1277.pdf The furnace manual notes that in two stage it still recognizes the v signal and can operate with a modulating t-stat. I guess my question is-should I run in modulating heat or two stage mode? I assume modulating heat is the real advantage with this furnace? Sorry for the ignorance-a definite learning curve for me. if you ever need to know anything about a cyclotron I can tell ya just about anything there.

 

[jmarro]

this is the actual furnace and t-stat http://216.122.22.11/FetchDocument.aspx?ID=8ac0a197-4ea2-449f-8b12-4d69a97a577a like i noted ruud had a sticker over the rogers one....

 

[crmont]

Thanks for the response. I am a bit confused- the t-stat is actually a rudd(has a rudd sticker over the rogers one on the backplate.) This is a link to the IF95-1277 I cannot find anything on the IF95-1282 http://www.ntsupply.com/files/products/1f95-1277.pdf The furnace manual notes that in two stage it still recognizes the v signal and can operate with a modulating t-stat. I guess my question is-should I run in modulating heat or two stage mode? I assume modulating heat is the real advantage with this furnace? Sorry for the ignorance-a definite learning curve for me. if you ever need to know anything about a cyclotron I can tell ya just about anything there.

I still think you have a multi stage thermostat there. Sure looks like the one in the picture though doesn't it...

Do you have a V terminal on the thermostat sub base? If not then you must use the timed multi-stage function of the furnace control board. If memory serves there are two ways to set the dips to accomplish different timings of the three stages. It's too late to dive into that. I'll d/l the manual and get back to you in the morning.

 

[crmont]

To clarify multi stage does not mean modulating. The stat instructions will specifically talk about modulating stuff if it has that function. (and the V terminal..)

 

[jmarro]

I still think you have a multi stage thermostat there. Sure looks like the one in the picture though doesn't it...

Do you have a V terminal on the thermostat sub base? If not then you must use the timed multi-stage function of the furnace control board. If memory serves there are two ways to set the dips to accomplish different timings of the three stages. It's too late to dive into that. I'll d/l the manual and get back to you in the morning.

Yes i do have a V terminal and it is used.

 

[crmont]

Yes i do have a V terminal and it is used.

Great! The factory dip settings for staging is what you want. Don't forget that you must use the V and he W terminal.

 

[karsthuntr]

BTW It's either single stage OR modulating with the factory dip settings. You see, the control board has a V terminal. This is the modulating input terminal. The board automatically goes into the mod function when it gets a signal on V. The V signal is whats called a pulse width modulating input. It must be used with the "V" terminal on the rheem/ruud mod stat. The first gen of this stat was kind of a POS but now it's a modified honeywell vision pro and it's quite nice.

It is three stage or modulating.

 

[crmont]

use the v and w terminals and it's modulating. Use just w and it's 3 stage. You dont have to change any dips, it's automatic.

 

[jmarro]

Fan control

A follow up question on this thread I made some time ago- Can someone educate me a bit on operation? As noted I am in Minnesota. It is 2 degrees F right now. Yes, I want to move. My air to air exchanger is set to run for 20 minutes every hour to keep the moisture off the windows and out of the house. It works well, but I have a hard time introducing all that cold air into the exchanger 30% of the time as it is only 85% efficient. So.. I have been playing with the fan settings and exchanger. I find that waiting for windows to "wet" before turning on the exchanger is a bad idea so I set it to run 20 minutes of every hour. Windows stay nice and clear. The exchanger instructions recommend having the furnace fan on constant while it is running. I noticed the "PROG" setting for the fan and wonder if this thing is smart enough to know when the exchanger is on? I know, probably a long shot eh. I guess my question is this- assuming the exchanger is on 30% of the time and the manufacturer recommends having constant furnace air flow during it's operation, what is the most effeciant fan setting? PROG or AUTO or On? I do not understand what the PROG fan setting actually does as this thing seems to take control set up as modulating. Thanks in advance- Joe

 

[docholiday]

is there a lower case h or a capital H in the furnace window when it runs?

 

[docholiday]

The fan program mode will run the fan if the furnace or air is off for a while. This just moves air once in a while.

There are classes available for the mod. Trial by fire usually doesnt work to well

 

[jmarro]

Upper case H

Docholiday- That would be an upper case H. So upper case H would show that the furnace is receiving the modulating signal and there are no active errors as opposed to lower case h showing quite the opposite. I am not an HVAC man I am a cyclotron man. I am learning. Not too sure what classes there are for the general public outside of the professional views expressed here.-

j