HVAC in ATTIC? (drains, sink, insulation, disposal)

[btuhack]

Originally Posted by chet everett

Good installers doing NEW CONSTRUCTION will run the condensate drain in a way that is NOT going to cause problems -- that might involve asking the plumbers to rough in a sanitary drain right under where the attic unit will be installed. Then the HVAC installers can plumb into that instead of some hokey "drip drain" that might can clogged.

There are 2 problems with your statement Chet.

All condensate, by code, must be "indirect waste" aka "drip drain", not directly coupled and using an air gap between the drain line and receptacle or drain to a garden location with an air gap.

A trapped floor sink receptacle may meet code in the attic but the problem with that is insulation has a bad habit of inadvertently finding it's way into spots where it doesn't belong. The receptacle could easily get plugged with insulation and go unnoticed until damage occurs.

An additional typical issue that might need some thought is that condensing furnaces, if that's being considered, need drains too. They must be terminated in a garden to meet code. Condensing furnaces produce water during the cold NJ winters. All wet components need some means of assuring that freeze damage doesn't occur....heat tape.

[joe moving]

I'm trying to understand how this house is laid out. Is each separate housing unit 1 floor of 2500 sq ft?

I would not put anything in the attic. As you mentioned, the attic should be outside of the envelope of the house and sealed and insulated very well away from the house. Duct work insulation is only something like R8 at best.

Have you looked into ductless mini-splits. They are inexpensive to install and very, very efficient. You'd probably need 2 units per housing unit (assuming each unit is 2500 sq ft), I'm guessing. About $10,000 total. These will heat and cool the house no problem. Example Fujitsu 15RLS3. Or Mitsubishi FH15.

[blazerj]

In my area, attic HVACs are pretty common. I have one. It's a bit of a pain to change the filters and I'd be afraid of putting a whole house humidifier in the attic (mostly from the water), but it's perfectly fine.

I think they do this so the venting is easier (the "ductwork tubes" are in the attic and the vents come down from the ceiling).

[Ted Bear]

25x100 2 story house, 2 family house. I just cant even imagine that, let alone worrying about putting the A/C unit in the attic (which people do all of the time, BTW).

[txfriend]

Originally Posted by SonorityGenius

Hey everyone - building a new home 25x100 - the builder is insisting that 1 HVAC will be in basement and 2nd will need to be in attic as the "pressure from rec room to 2nd fl" will not work.. now call me crazy but I have lived in 2 family homes and rented few and ALL HVACs have been in basement.. I am uncomfortable with it in attic after reading so many horrible experiences people have had with leaks, high bills since I know it wont be insulated well etc

What are your thoughts? I dont know the height from plans but its a standard 2 fam home 25x100 lot 36' max with roof pitch 5'

Here in very hot Texas we have no basements and many HVAC systems are in the attic. I have two, one a 4 ton unit and the other a 3 ton unit. In the 33 years of living in this 3200 sq ft house I have never experienced a problem. My units are checked and serviced annually. I have a high roof.

[Threerun]

I've had two houses that had units in the attic and in the basement. No problems.

Made for an efficient system.

[life4orce]

I have a 2 story colonial with attic and basement in New England. We have a multizone forced hot water heating unit in the basement with the AC blower in the attic and the condenser outside, like many others have stated here. The house was built for us 12 years ago and has been working very well.

[SonorityGenius]

Thank you all!! So the only downfall is proper attic insulation, drain, and filter changes! I can manage that.. I just was so against it and wanted both in the basement together

[Listener2307]

Originally Posted by SonorityGenius

Hey everyone - building a new home 25x100 - the builder is insisting that 1 HVAC will be in basement and 2nd will need to be in attic as the "pressure from rec room to 2nd fl" will not work.. now call me crazy but I have lived in 2 family homes and rented few and ALL HVACs have been in basement.. I am uncomfortable with it in attic after reading so many horrible experiences people have had with leaks, high bills since I know it wont be insulated well etc

What are your thoughts? I dont know the height from plans but its a standard 2 fam home 25x100 lot 36' max with roof pitch 5'

It's cheaper to put it in the attic. In your area (if New Jersey is correct) a return is required in every room. I know it is that way in Chicago, and I know that is NOT a requirement where I live.
So every room on the 2nd floor MUST return to wherever the unit is. That's a lot of duct work if the unit is in the basement, and you have probably already agreed on a price for the house.

I don't know if you have a lot of latitude at this point, and I don't KNOW that a return is required in every room. You'll need to check that out, and I would do it by looking around at various houses to see if every room has a return.

FWIW: I HATE the way we do it here in the South. We have one centrally located return to serve the whole house. I hate it; it's noisy and inefficient. But that's what we do.
If there is anything I hate more than our "one return" system it is placing a cooling unit and it's distribution duct work in the hot attic. If I had anything to say about it, I wouldn't do it.

[sedimenjerry]

Ours is set up in the attic as well. We have a basement as well. First floor is handled down there. 2nd floor is handled in attic.