AU_Prospector
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Hello,
I have two combination heat pump/ac systems in my new to me home. A smaller unit controls the upstairs and a larger unit controls the downstairs. They both consist of a long distribution tunnel and several round flex duct lines that run to the vents in the ceiling upstairs and in the floor downstairs.
All flex duct is a combination of 6" and 7" round and insulation rated R-4.2 is covering it.
Some flex duct runs are short and some long at just about 30 feet.
The upstairs unit has a metal distribution tunnel that is 12 feet long and has
9 ducts coming off of it. The flex duct is laying on top of and in some places halfway buried in the blow in fiberglass insulation in the attic. The distribution tunnel appears to be lined with insulation. I pulled off a duct and was able to see the words CT INSULATION 1/2". There was more, but I couldnt see it. The insulation appears to be a black dense matted material with the feel of rough felt.
The downstairs unit is in my crawlspace. It has a metal distribution tunnel that is 24 feet long which tapers down to 11" square at the end. It has 15 ducts coming off of it. The tunnel is also insulated as described above. All flex duct in the crawlspace is hanging from the floor joists and is otherwise exposed.
Things I have done so far in the crawlspace.
1) Straightened out the flex duct and re hung it to create as straight of path as possible.
2) Reconnected loose duct to the distribution tunnel as they were not all tight.
3) Some of the longer runs involved the joining of two ducts to create a longer one. This was not done cleanly and created restrictions in the line. I have fixed this to the best of my ability.
4) Retaped some of the seams in the distribution tunnel as some were leaking.
I am considering two new steps... 1) Wrapping insulation around the distribution tunnels in both the attic and the crawlspace and securing it with HVAC tape. 2) Adding more blow in fiberglass insulation in the attic and burying the flex duct to add to its R-Value.
Is it okay to bury the flex duct in the attic with pink blow in insulation? Added insulation in the attic is a good thing, further insulating the duct work is a bonus right?
Will wrapping the distribution tunnels increase the effeciency enough to warrant the cost?
Thank you if you have made it this far. I can be a bit long winded, but want to explain the situation and what I am doing as much as possible.
Prospector
I have two combination heat pump/ac systems in my new to me home. A smaller unit controls the upstairs and a larger unit controls the downstairs. They both consist of a long distribution tunnel and several round flex duct lines that run to the vents in the ceiling upstairs and in the floor downstairs.
All flex duct is a combination of 6" and 7" round and insulation rated R-4.2 is covering it.
Some flex duct runs are short and some long at just about 30 feet.
The upstairs unit has a metal distribution tunnel that is 12 feet long and has
9 ducts coming off of it. The flex duct is laying on top of and in some places halfway buried in the blow in fiberglass insulation in the attic. The distribution tunnel appears to be lined with insulation. I pulled off a duct and was able to see the words CT INSULATION 1/2". There was more, but I couldnt see it. The insulation appears to be a black dense matted material with the feel of rough felt.
The downstairs unit is in my crawlspace. It has a metal distribution tunnel that is 24 feet long which tapers down to 11" square at the end. It has 15 ducts coming off of it. The tunnel is also insulated as described above. All flex duct in the crawlspace is hanging from the floor joists and is otherwise exposed.
Things I have done so far in the crawlspace.
1) Straightened out the flex duct and re hung it to create as straight of path as possible.
2) Reconnected loose duct to the distribution tunnel as they were not all tight.
3) Some of the longer runs involved the joining of two ducts to create a longer one. This was not done cleanly and created restrictions in the line. I have fixed this to the best of my ability.
4) Retaped some of the seams in the distribution tunnel as some were leaking.
I am considering two new steps... 1) Wrapping insulation around the distribution tunnels in both the attic and the crawlspace and securing it with HVAC tape. 2) Adding more blow in fiberglass insulation in the attic and burying the flex duct to add to its R-Value.
Is it okay to bury the flex duct in the attic with pink blow in insulation? Added insulation in the attic is a good thing, further insulating the duct work is a bonus right?
Will wrapping the distribution tunnels increase the effeciency enough to warrant the cost?
Thank you if you have made it this far. I can be a bit long winded, but want to explain the situation and what I am doing as much as possible.
Prospector