Greetings. Long time lurker, first time poster.
The lowdown: Bought a 1984 built foreclosed 1.5 story home last year. Did an energy audit and found out the house leaks like a sieve. Had all new windows put in which helped tremendously now I need have the very leaky, old return ducting done. So far I have had two contractors come out and bid.
The equipment (existing):
Trane XB Downdraft Furnace (Model #TDE1B100A9451AB)
Trane Coil (Model #4TXCB048BC3HCAA)
Filter box: 3 - 10x30x1 filters
Trane 4 ton outside a/c unit.
Supply ductwork in slab, no dampers
1 - 16x32 return in central hallway that is nothing more than a joist cavity running back to a duct board end with two flex duct attachments, once which is broken loose. Can actually feel cold air come back once furnace shuts off.
1 - 12x12 return in upstairs master bedroom. Master bedroom takes up half the upstairs. Hallway from bedroom to master bath overlooks living room (22 foot vaulted ceilings) with 3 shutter doors.
(A) $$$ : 1st Contractor came out, stated that the return ducting from the box into the unit was fine. Would replace the box and flex duct and upgrade from 2 - 16" to 2 - 18" and fix broken attachment on return ducting. No calculations, nothing else but a visual.
(B) $$$$: 2nd Contractor came out. Inspected all the registers in the rooms, took measurements, used an Ipad with some sort of software on it to calculate and offered the following:
- enlarge the two returns to 20x30 and 14x14
- replace furnace return plenum
- run new 20" diameter metal ducting from plenum to roof rafters, split into two 16" diameter metal ducts to go around roof rafters (see picture 3) back to 20" and straight to return joist run. All insulated and hung properly.
- remove box and instead have master bedroom return "t" into main duct with damper
- for extra $$$ add two more returns to back two bedrooms feeding into main return duct.
The pictures of what I am dealing with:
1st picture is looking at the ductwork coming from the top of the furnace closet.
2nd picture is looking under the roof rafters to where the existing flex duct ties into the joist area. (Have to remove my cover front patio ceiling to get to this area, adding $$$ to the job)
3rd picture is looking at where the flex duct from the main return joins up with the master bedroom return. (yes it is noisy). To the right of that is where the roof rafters drop down to the top plate and tie in to the covered patio roof. No way they can mess with the rafters or top plate which is why they have to split the ducting. Only room enough for 16"-18" ducting, between the rafters and the top plate.
4th picture is a close up of the box.
5th picture is where the duct drops down into the unit.
6th picture is looking up inside the box that's on top of the filters.
Need to know if option 2 is a good enough deal to go with. Option 1, I know, from what I learned here, is not the answer. The hair on my neck (what little is left) stood up when I heard those words "I've been doing this for years".
Are there any other questions I need to ask? Anything anyone sees could be done differently ? I probably will end up getting a 3rd bid but I travel for a living and I don't have much time to deal with this, nor a ton of money to throw at it wastefully. (Windows are expensive!)
Next up is having the roof replaced along with the decking. Ugh.
I have appreciated all the information I have garnered from this site and all the amazing professionals here. Helps make informed decisions. You are all a credit to your profession. Yes, you are right, this stuff is NOT easy. Dont know how you guys do it.
Thanks again for any and all input!