Thanks, guys, for all the great input. One more question:
I've done a lot of online searching for good examples of a sheet metal equivalent to this ugly mess masquerading as a plenum (that WILL be completely scrapped and replaced, one way or the other). So far, I haven't been able to find anything even close. The closes I can find are bottom plenums designed for large rectangular ducts that come down the side of the furnace. Can anyone refer me to pictures, specifications, etc so I know what they SHOULD be specifying?
Are there any specific dimensions, proportions, minimum volume, etc that I need to look for?
The plenum will be custom fabricated by the contractor.
X2, it will just be a rectangular metal box the same size as the bottom of furnace and as tall as the space permits
Originally Posted by skibme
Both of my remaining bidders have proposed different solutions. One wants to use the existing box and line it with sheet metal (apparently he missed the part about how I wanted no part of that thing to be reused). The other contractor (who's in the lead at this writing) proposes scrapping the existing mess and building a new wooden return box (apparently he missed that I specified a sheet metal return box). Sigh.
It doesn't seem to me like a sheet metal box would be such a big deal that they'd want to avoid it--particularly since I've spec'd replacement of the existing 14" round return duct with 16" round (metal, not flex) and replacement of the 20x20 filter grille with a 20 x 25. I'm surprised that they're avoiding it. Am I wrong.
No disrespect to the pros on this forum, but if we end up with a wooden return box I'll build it myself. I'll do a much nicer job. :)
UPDATE: Heard back from contractor and learned that he'd specified a wooden box because they had one on hand that they'd built for a different customer but never used it.
He'll be installing metal. No problem.
I thought that since I posted the "before" picture at the beginning of this thread, I should post the "after" as well--and the before again, just for the sake of convenience.
The contractor began working on a Monday morning ten days ago with a plan to replace the upstairs unit that week (Mon-Wed scheduled) and the downstairs unit the following week (Mon-Wed). I had them demo the downstairs on the first day so I could get into the space and clean it up. The sheetrock behind the furnace was a disaster, and I removed and replaced most of it. While I had the walls stripped down, I framed for the larger (16") return and had the contractor rough in the flue and fresh air. I also moved the line voltage disconnect to a more appropriate place and left them an armored pigtail (I HATE using romex in the open!) When they arrived on this past Monday to begin the downstairs unit, the space was clean, painted, and so nice the contractor barely recognized it (it was really nasty after the old Lenox left the room).
It'a qwednesday afternoon, the Contractor just left and my check-writing hand still stings, but the result is well worth it. Can you tell which picture is "before" and which is "after?" :)
We've had an XV95 running upstairs for about a week now, and we love it. The pair of systems wasn't a cheap date, but they're worth it!