Heat exchanger in a Goodman furnace?

[Brian_42]

Hello everyone, I recently purchased a larger Central Boiler (5036 - I think?), anyhow, poured a pad, bought the good Thermopex from CB, got everything plumbed inside and out, and now I just have to cut into my furnace and install a heat exchanger. I took the back covers off my Goodman 95% efficiency furnace last night, with the end in sight, and now I need some help. The AC exchanger (terminology?) is triangle shaped, and the top is above my ductwork, I called my furnace guy, he said I cannot install it under the AC unit (only a couple inches clearance anyhow), so now I've spent a fortune, and a lot of labor...
Has anyone ran into this issue, and if so, how did you go forward?
Any advice is very much appreciated, thanks in advance.

 

[dave_dj1]

My first thought would be to install it under the ac unit if possible. I have read that installing it above can cause it to freeze in the summer if not used.
I know you said it didn't have much space below. Is it possible to add to the height of the plenum? This would be my first choice.

 

[rancher2]

I have two Goodman furnaces in my house not that brand makes any difference. One has a cased AC coil the other has the coil in the plenum. The one with the cased coil I put the heat exchanger for my Garn above the AC coil. The other furnace I went under the AC coil as when I installed the heat exchanger I was also replacing the furnace with the Goodman and it was a lot shorter that the furnace I was replacing. I just made a short plenum to take up the space between the new furnace and the old plenum. I popped rivet aluminum angle in the plenum and the heat exchanger sets on top of it. Both have been in for 10 heating seasons with no issues with the heat or the AC in the summer.

 

[brenndatomu]

Worst case scenario, put the new HX coil in it's own plenum, tie it into the existing ducts/plenums "parallel" style...might hafta find a cheap used furnace blower on CL to put behind the HX...but you can certainly make this work...many ways to skin this cat.
Have any pics of what you are dealing with here? (existing furnace/ducts)

 

[Mustang71]

There is no reason you cant move the ac coil up if you have the height and put the new HX below it. Find a heating guy who isn't lazy and have him do it. I dont see y you cant put it above the ac coil if it's a distance away like in the ductwork. Dont set it right on top of it because the restriction could possibly freeze it up.