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I'm trying to determine if I have a leak around my central AC unit. Basically when the unit is on, I feel cool air blowing outside the "furnace plenum" as I believe its called.

If you look at this picture, I think the air is coming from where the drain hose connects to the unit.

enter image description here

So my questions are:

1) Is this normal for air to be blowing out here

2) If not, is there a way I can seal it better?
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up vote 1 down vote accepted

That picture is kind of unclear but it certainly looks to me as if the drain (and maybe the whole a/c) was added as a retrofit to a furnace - the hole is uneven looking to me - sloppy. I have something similar myself, in fact.

In answer:

1) No, it's not normal - it' a waste. Air exchangers that are built to do both jobs do not have these kinds of gaps.

2) Yes - cut a piece of plastic to fit over the hole as much as possible. Seal in place using METAL tape (not duct tape), closing up all the remaining gaps.

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Shouldn't a gas line to a furnace be a solid line and not flexible? Thought that was a big no-no. – lsiunsuex Jul 6 '12 at 19:28
Thanks for the info. I went ahead and sealed it off with some duck tape (I have to get some real HVAC tape). And no actually its not a retrofit, it was installed with the house which is only 8 years old. Thanks – JavaKungFu Jul 6 '12 at 19:30
@Mario - as I understand it, no - flexible gas lines are perfectly legal in many districts. – The Evil Greebo Jul 6 '12 at 23:42

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