PVC drain pipes leaving HVAC unit
#1
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PVC drain pipes leaving HVAC unit
Hey all. I've found a few threads on this but nothing seems to fit my setup enough to feel confident to fix this yet.
As you can see in the photo below, there are two PVC pipes leaving the unit. One drains into the floor, and the second is just a small elbow that is open facing up.
My question is this. Should it remain open, or should I cap it? The reason I ask, I'm getting a good amount of water coming out of it when the unit is on, enough to fill that little tan-colored tray that I set underneath it in the time span of a few hours or so. I noticed it a few weeks ago, and the water was dripping into the unit itself. (underneath that tan tray is a vent). I don't want to cause any damage.
Anyone have any insight to this? Thanks!
-Adam
As you can see in the photo below, there are two PVC pipes leaving the unit. One drains into the floor, and the second is just a small elbow that is open facing up.
My question is this. Should it remain open, or should I cap it? The reason I ask, I'm getting a good amount of water coming out of it when the unit is on, enough to fill that little tan-colored tray that I set underneath it in the time span of a few hours or so. I noticed it a few weeks ago, and the water was dripping into the unit itself. (underneath that tan tray is a vent). I don't want to cause any damage.
Anyone have any insight to this? Thanks!
-Adam

#2
The home made P-Trap on the floor is full of slime causing this back up.
Remove that pvc cap and connect your shop vac to the drain line to clear it.
If possible connect the shop vac at the end of the drain as well. Flush with water after you clear the drain.
Remove that pvc cap and connect your shop vac to the drain line to clear it.
If possible connect the shop vac at the end of the drain as well. Flush with water after you clear the drain.
#4
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I assume it is blowing air and water out the top, not overflowing. If so, the easiest thing is to just cap it off.
With two openings one is the primary drain and one is the overflow. The overflow should only have water coming out if the primary is blocked. The overflow is capped off in a lot of cases. In other cases an overflow switch is attached to shut down the system when it senses water. Last option is to pipe it out to an obvious place to let the homeowner know that there is a problem when they see a drip. In no case should it be open like yours without a pan underneath.
Usually the overflow is slightly higher than the primary drain port. From the picture the right opening looks to be higher that the left. If so the drain should be moved to the left opening to keep water from pooling in the air handler.
With two openings one is the primary drain and one is the overflow. The overflow should only have water coming out if the primary is blocked. The overflow is capped off in a lot of cases. In other cases an overflow switch is attached to shut down the system when it senses water. Last option is to pipe it out to an obvious place to let the homeowner know that there is a problem when they see a drip. In no case should it be open like yours without a pan underneath.
Usually the overflow is slightly higher than the primary drain port. From the picture the right opening looks to be higher that the left. If so the drain should be moved to the left opening to keep water from pooling in the air handler.
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Astuff, I believe you're onto something here. I capped off the open overflow pipe and more water was being pushed through the primary pipe.
Here's a photo of my old condo unit below. The overflow is capped and has a safety switch which is what I think you're talking about. I've never noticed it or seen one until now. Is it okay that I don't have a safety switch?
Here's a photo of my old condo unit below. The overflow is capped and has a safety switch which is what I think you're talking about. I've never noticed it or seen one until now. Is it okay that I don't have a safety switch?

#7
Your primary must be clogged, otherwise you won't see water in the secondary. Are you sure you checked the whole primary line, including the drain line opening inside the air handler?.
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I'm not 100% sure on the whole primary being unclogged. I just checked from the cap and down. I will try and pull it apart tonight, I'm assuming the pieces are glued together so I may try another method. Thanks again.