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englewood1 09-16-2007 12:30 PM

Replacing an 20 year old gas forced air with a 95% 2 stage goodman, goodman 40" tall,
The goodman is 40" tall and the old one is 55" tall. Probably need a return plenum and support 15" high to fill the gap. Do they make a kit with the sheet steel pre-bent for connection or is this a custom job?

bluesy 09-23-2007 08:24 AM

I just did the exact same thing here. I got a 40" in place of a 54" furnace by using a "transition kit". The furnace I ordered came with a video that, if you're moderately handy, you can easily follow to successfully transition from different heights/sizes. The kit is just 4 pieces of sheet metal and 8 "connectors". You'll need tin snips. Had to run 2 PVC pipes for intake air and exhaust- the 95%ers - a bit of a chore but not too bad. It's a Goodman, bought on line. Only ran it a few times since the weather isn't bad here yet; but I'll tell you that there's more condensate coming out than I expected. Anyways, the transition from different heights and sizes is not difficult to do.

englewood1 09-23-2007 01:11 PM

Where did you get this video and kit? My return comes in through the lower left side, so I need a plenum without a top and I cut out a side entrance for the existing return duct. I am also not sure where the filters go. I would expect clips to hold the filters below the blower, but none are there.

bluesy 09-23-2007 02:13 PM

here's a link...
.....these people ( extremely helpful on the phone. My existing return hooked right up. I used the transition kit to fill the void between the old 54" unit and the new 40" one. A transition kit might also be used for the return side. My filter is still in the old return- as it was before. Take the time to go through their website topics. There's a lot of information there.

bluesy 09-23-2007 02:15 PM

Oh, yeah..
..the video came with the new furnace and covers transitions, humidifiers, air conditioning, etc. The transition kit also came from Alpine.

englewood1 09-23-2007 03:35 PM

Thank you very much! Did you mount your unit on the return air plenum so it could reach the supply duct? I am going to suspend the condensate drain and AC coiling coil by several hanging wires. I am an electrician, so the electrical side is easy. Where did you mount the filters?

bluesy 09-23-2007 08:07 PM

...I set my furnace so it lined up with the return air duct, cut the hole in the side of the furnace, folded "tabs" outward and connected the return side up. The furnace is on 1 1/2" "legs". That left a 14" gap between the top of the furnace and my existing supply plenum. That's where the transition kit fit in. The filter fit in the old existing return just like it did before. Hope that helps.
On another note, I took the time to seal every spot that ANY ductwork joined to another section. I couldn't believe how many very small leaks there were. I sealed both the supply ducts and the return ducts wherever I could get at. A government study revealed that as much as 20% of supply air is not going all the way through to ones registers. Returns are just as bad- The link to that study is long gone- but believe me, they spent some money (it is the government after all) coming up with the 20% "average". Seal everything you can- and not with insulation- the leaks have to be sealed with mastic (or the proper tape) before insulating.

englewood1 09-23-2007 08:52 PM

Did you have a cooling coil and condensate drain pan above the furnace? I don't know what supports this coil and pan, I think it just sits on the furnace heat exchanger, but I don't know.

bluesy 09-24-2007 08:11 AM

...I have a cased coil that mounts directly to the top of the furnace. Sounds like you have an uncased coil. That is usually setting on 90 degree rails that are mounted to the inside of the plenum. It also sounds like you are wanting to lower the existing plenum and coil 15
inches to the top of the new furnace. I really don't know how far above the furnace the coils can be located before cooling capacity might be hindered. You could strap up the plenum and transition the now existing gap to the top of the furnace Or...cut the plenum above the coil, lower and transition that section to the top of the furnace then transition gap that's above that-if your refrigerant lines are long enough. If you can leave the coil 15 inches above the furnace, that sounds like the way to go. Only one transition to make. No coil moving, etc. Question is: can the coil be 15" above the furnace and cool properly? I don't know. Maybe someone might field that in a separate post?

bluesy 09-24-2007 08:16 AM

Now that I think about it, I suppose you could raise the new furnace 15", and cut off and transition your return to the furnace. Might be easier. Sounded like that was your intention.

englewood1 09-24-2007 09:01 AM

The coil was added on in 1988. As long as its supported and the condensate is drained properly, the location won't be a problem. I ordered the kit and the straightener for 90 degree bends. The old filter was located in the upper compartment cover door. I probably need to install the filter slanted with clips to hold it, does the video cover this? (This is a video from Alpine Air)

bluesy 09-24-2007 09:17 AM

The video didn't mention anything regarding filters. Mine is a slide in... slides into a slot where the return joins to the furnace. If I was more computer literate, I'd attempt to send you the video clip in an email.

MikeD49519 09-25-2007 11:37 PM

Bluesy... Your Alpine experience...
Hey Bluesy...

I have a few questions about your experience with buying your
equipment from Alpine Home Air...

I'm looking at getting a heat/ac package from them - 95% varispeed
gas upflow with a 14 seer 2.5 ton AC.

Did you use their contractor assistance program? If so, was it any help?
I plan on doing most of the install myself, then having a local contractor
inspect it and startup. My fear is that no contractor will want to touch
it if they did not do the whole job themselves.

How was delivery? was the equipment boxed up well?

How good are the videos? lots of detail, or did it leave you with alot of
questions? Did you have any other books or manuals on the subject?

Did you have to get a permit in your area? If so, did they frown on you
doing it yourself? Did you have to put in a chimney liner for your water
heater? My local building inpector says it's code because of the reduced
draft from no furnace vent pipe going to the chimney anymore.

Thanks for your time!

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