A-coils Upside Down

[hcong]

The indoor evaporator coils is cold on all parts of the coil, so no matter which way the air runs through them, they should cool the air.

Now the refrigerant travels through the coils in the same direction so certain set-ups will give slightly better cooling, but the manufacturer knows best and everything should be installed per the instruction manual.

Also, how do you put an extra drain pan on a downflow system without blocking the duct if the coil is installed upside down?

[hvacrmedic]

If one were to install it upside down, would you expect any cooling?

I've seen an inverted A coil. I don't remember the brand. It had a small plastic drip pan under it, factory stuff all the way. No reason it shouldn't work. It's no different in principle than a diagonal slab coil except that there's two of them at opposite angles butted together sharing a single drip pan. I'm still wondering though, if what you saw was actually an Air Seal Assembly, which resembles a pan but isn't. It's there to prevent condensate blow-off, and is removed on downflow applications. A downflow kit is required for that application. The kit contains a flat sheet metal plate that replaces the Air Seal Assembly.

[brucezas]

The indoor evaporator coils is cold on all parts of the coil, so no matter which way the air runs through them, they should cool the air.

Now the refrigerant travels through the coils in the same direction so certain set-ups will give slightly better cooling, but the manufacturer knows best and everything should be installed per the instruction manual.

Also, how do you put an extra drain pan on a downflow system without blocking the duct if the coil is installed upside down?

The extra drain pan was much smaller than the other one. Not sure exactly how it was mounted. Do you find it impossible to believe that once upon a time there was a coil designed to work both downflow and upflow, but where Carrier expected you to flip it to use in the downflow configuration? I think that I will try to contact the owner that explained that to me and review the details with him. BTW, when we tried to use it in the downflow configuration without flipping it, with it's normal drain pan on the bottom, water blew or got sucked around the pan and into the duct. That makes sense if it wasn't intended to work that way.

[hcong]

The coil your mention might not be a "multipoise" coil... I wonder how Carrier fixed the water being blown into the ducts problem with the new multipoise coils.

[brucezas]

The coil your mention might not be a "multipoise" coil... I wonder how Carrier fixed the water being blown into the ducts problem with the new multipoise coils.

We were able to fix it with some modifications. Iirc, the contractor made some little brackets to hold the pan up a little higher.

[comfortdoc]

What is the model number of the coil?

[brucezas]

I've seen an inverted A coil. I don't remember the brand. It had a small plastic drip pan under it, factory stuff all the way. No reason it shouldn't work. It's no different in principle than a diagonal slab coil except that there's two of them at opposite angles butted together sharing a single drip pan.

Thank you. I thought I was losing my mind there for a minute. I hate to not know what I'm talking about.

I'm still wondering though, if what you saw was actually an Air Seal Assembly, which resembles a pan but isn't. It's there to prevent condensate blow-off, and is removed on downflow applications. A downflow kit is required for that application. The kit contains a flat sheet metal plate that replaces the Air Seal Assembly.

I think I know what you mean because I think I just saw a picture of it. I can't find it again. I was looking for proof of what I was talking about. I didn't find that, but I saw a shallow pan looking thing with sloped edges on top of an old coil. Mine was an actual pan with right angle sides, and an attachment for a hose, and we used it as a fully functioning pan after a few mods to keep water from blowing around it.

[hvacrmedic]

Thank you. I thought I was losing my mind there for a minute. I hate to not know what I'm talking about.




I think I know what you mean because I think I just saw a picture of it. I can't find it again. I was looking for proof of what I was talking about. I didn't find that, but I saw a shallow pan looking thing with sloped edges on top of an old coil. Mine was an actual pan with right angle sides, and an attachment for a hose, and we used it as a fully functioning pan after a few mods to keep water from blowing around it.

The air seal assembly does have an attachment for a hose. The hose slopes down and drops into the horizontal drip pan. There's a hose tap on each side of the air seal assembly, one for horizontal left and one for horizontal right configurations.