Alternatives to gas forced air plenums?
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To succesfully remodel my 3 level split ranch from a 3 bedroom,2 and 1/2 bath to a 4 bedroom, 3 bath I must get rid of the forced air plenums. The return rises up the middle of the house and eats up the square footag I need for the expansion. Plus the space used by the furnace will allow me to expand the half bath to a full bath. My solution so far is to switch from a standard gas forced air gas furnace unit (AC over furnace) in the laundry room (future space for 4th bath) to a high velocity system (like UNICO or Spacepak) in the attic. Although the high velocity system allows me to get rid of the plenums (flexible insulated supply is run through attic and walls ending in 4″ openings in ceiling and lower wall corners) which will give me the building space I need there are some serious trade offs:
Replacing the current gas furnace and AC unit runs around $7,000. The high velocity unit will cost around $16,000.
The high velocity unit uses a heat pump/electric coil combo for heat.
I’m looking for any expereince with high velocity systems or other alternatives.
Thanks,
Replies
Greetings Carlos,
This post, in response to your question, will bump the thread through the 'recent discussion' listing again.
Perhaps it will catch someones attention that can help you with advice.
Cheers
"Live Free,
not Die"
Where are you?
Cool air, which is what you will get with a heat pump, is hard to live with at high velocities.
If I could possibly do it any other way I would not put any equipment or ducts in the attic space.
IMHO $16,000 is a ridiculous amount to spend to H&AC a 4BR house.
I'm in MD where the concern is heat and high humidity. And yes, you're right this is a high price but it get's me one extra bedroom and bath vs an addition to the house which would cost much more. Thanks for the comments.
Carlos
Hi. I'm in the process of designing a timber frame house and have started to look at heating/cooling options. I came across SpacePak (due to its small duct size) on a site called ACdirect and after some rough calculations, it seems I could buy the equipment I need and install it myself for about 6 grand. I have limited knowledge of these high velocity systems so I have some questions.
First, I haven't read much about the heating nature of these systems, only the cooling. I assume the are all electric heat as well as cooling?
Second, I don't see much mention made of returns. I assume you still need a return for each room. All I ever see mentioned is one big central return. Is this possible? Any comments would be helpful.
-Mike