AC unit drainline

[mridgeelk]

Is this drain line proper as installed? I don't see the need for a trap effect here. Ed

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[Billy_Bob]

I assume that is on a roof and it is draining on the roof?

Otherwise I think the trap is a clever idea in these days of high energy costs. An open drain will let cold air flow to the outside. I suppose it is a good idea to keep all the cold air where it belongs!

[Neal Lewis]

Originally posted by Billy_Bob

An open drain will let cold air flow to the outside. I suppose it is a good idea to keep all the cold air where it belongs!

Billy, it could be sucking air into the unit, depending on the type of system.

I usually see the traps on package roof top units.

[Bill Kibbel]

Every unit needs a trap.

Originally posted by Neal Lewis

...it could be sucking air into the unit, depending on the type of system.

Like this:

[Bryan]

Condensate water is very acidic and drain lines on metal roofs should be ran to the gutter or off of the roof system to prevent corrision of the roof deck.

Bryan

[caryseidner]

I don't think that is actually a metal roof. It looks more like the substrate.

I've seen thousands of PVC condensate drain lines that are run all the way to the roof systems drainage point. All they end up doing is prohibiting the flow of rain water/snow melt from reaching the drain or gutter.

The drain/trap look fine. It will probably be broken off by the time the roof is finished because roofers aren't very dainty.

[hausdok]

Originally posted by Bryan

Condensate water is very acidic and drain lines on metal roofs should be ran to the gutter or off of the roof system to prevent corrision of the roof deck.

Bryan

Furnace exhaust condensate maybe but how could AC condensate be acidic; it comes from the air around you.

ONE TEAM - ONE FIGHT!!!

Mike

[msteger]

I would also call it out, based upon your photo, and recommend the drain be extended to the roof edge.

I thought the roof was also metal, from the photo.

[Bill Kibbel]

That doesn't look like a condensing furnace. A/C condensate is not acidic.

That's a metal roof with an "R" Panel profile, not corrugated decking.

[Brandon Whitmore]

If that is a metal roof as it appears to be, I would be pretty concerned about the flashing details (or lack thereof) at the duct penetration

[caryseidner]

I believe it is a metal deck and not a metal roof. The structure doesn't appear to have enough slope to remain watertight with a metal roof system. It's a limited view and difficult to see, but the reveal on the curb is consistent from left to right. As the flutes are running from left to right as well, we should see the deck sloping on the side of the curb.

Just deducing from what I could see. I'm sure we would all be able to tell for sure if we had a larger field of view or were on the roof.

So what was it Ed?

[Phillip]

It looks like a metal Deck where they will more than likely pour light weight concrete on it and then install a build up roof or a single ply roof .

[mridgeelk]

It is a completed metal roof. The formed metal ridge is misaligned in some locations and needs to be properly sealed. the building is less than one year old. The current owner said he had the builder back for repairs on the roof. I called out that the sealants were applied inconsistently as gaps in the ridge were not all sealed. It is an AC/furnace unit the first I have seen. I recommended that a qualified contractor review the system. And I recommended to me that I get much more familiar with this type system

Originally posted by caryseidner

I believe it is a metal deck and not a metal roof. The structure doesn't appear to have enough slope to remain watertight with a metal roof system. It's a limited view and difficult to see, but the reveal on the curb is consistent from left to right. As the flutes are running from left to right as well, we should see the deck sloping on the side of the curb.

Just deducing from what I could see. I'm sure we would all be able to tell for sure if we had a larger field of view or were on the roof.

So what was it Ed?

[Thor]

The trap is there to offset the negitive pressure of the duct system . Without the trap the water would be held in retention in the drain cond pan with the possibility of overflowing down the RA duct.