Air Conditioning - Condensation drain/pipe - sitting water

The AC unit's condensation pipe does not angle down far enough, and it goes horizontally from the pan at the bottom of the unit, so water does not drain. It just sits there. There is all this nasty orange stuff in it, and is getting clogged in the pipe. Water still flows, but only a little bit.

This has cause the coils to become smelly. Nothing i have done will remove all the orange stuff. Not even bleach.

What should i do?

BTW, this is an apartment so i can't do much in the way of DIY.

There shouldn't be any water in the pan under the air handler, if so, check the main drain from the coil, or the pan is rusted.

The problem is that the pan is directly connected to the pipe and coil. See this picture for clarity

http://i9.************/4i57hpy.jpg

I only saw the drain from the coil. so you are saying that this drain is tied into the pan under the air handler?

Yes it is. Here is the air handler, sitting on the shelf, with the pipe connected to the drain pan.

http://i7.************/30t6ow7.jpg

And here is one showing the orange colored water that is idle in the pan.

http://i15.************/47u2620.jpg

If I looked at the picture's right. I dont see the filter. But if the air goes into the coil there you have to have a P trap on the drain line. That is what could hold the water in the pan and make it smell . Or does that drain line go right into a sewer vent stack???

If I looked at the picture's right. I dont see the filter. But if the air goes into the coil there you have to have a P trap on the drain line. That is what could hold the water in the pan and make it smell . Or does that drain line go right into a sewer vent stack???

I took the filter out so you could see behind it where the pipe connects to it.

What's a P trap? If it would get rid of the orange stuff, please tell me!

Anytime a unit like yours sucks the air over the coil It like holds the water in the pan there and not much gets out. You would like cut that pvc line as it goes over to the left and with 4 90oL Make a big U. Are you can buy a pvc trap for this at Lowes and Home depot that will work. You didnt say what does the other end of that pipe go to or in?????
The trap should let the water run out the drain pan for you. It still has to run down hill some

ED ;)

The problem is that the pipe entrance from the drain is elevated from its ground level, so the water must be a certain height to reach it. The water will drain while the unit is running, but then, when it falls below that level, it just sits.

I have tried tilting the drain toward the pipe to no avail.

On most house units, the pipe is at the bottom of the pan and it is angled toward the pipe, so water always flows through. Apartment upflow units like mine are sitting on a metal slab (not permanently) and the pipe cannot go downward from the unit.

I have tried putting in tablets, cleaning it with a brush, pouring soap and bleach in there, and spraying coil cleaner. It goes away for a while, but the next day, all the orange rust is sitting in the pan again. I try to suck the water out with a syringe squeezy thing but it just comes back the next time the unit runs.

Help! The smell is nasty and the landlord doesn't care!

If you want an example of what it smells like, leave an aluminum cab of shaving cream in a bowl of water for a month, and then smell it.

Water has to drain downhill. The only solution I can see is raising the coil/air handler about one inch. I understand it may not be possible without a lot of work, but I think that's the only solution.

While bleach can remove the smell, it will not stop rust. In fact, bleach is an oxidizer and will cause more rusting.

Good luck.

Raising the unit is not an option since the ducts touch the ceiling of the small cabinet it is in (the apartment's ducts hang under the ceiling, not go through it like in a house).

So what can i use to get rid of the rust? I wouldn't mind sucking the water out if it wasn't rusty.

I wish they weren't idiots 17 years ago when they thought of designing air drain pans with unanodized aluminum that can rust.

i went back to your pic I still say its that you dont have aP trap there So the water can get out of the pan

I agree too, Ed, but can you tell if there is sufficient space below the left/right horizontal drain to even put one there? I wonder where it goes once it gets out of sight...

OTOH....once the fan cuts off wouldn't you think the condensate would then drain out? If it doesn't then it's not because of a missing p-trap, don't you think? It would be because of insufficient gravity, slope, or blockage. Somehow I think it is a combination of the latter two.

OTOH....once the fan cuts off wouldn't you think the condensate would then drain out? If it doesn't then it's not because of a missing p-trap, don't you think? It would be because of insufficient gravity, slope, or blockage. Somehow I think it is a combination of the latter two.

This is exactly right. There is no enough sloping to the drain, and the pipe is too high above the water level to let water exit once it gets below the pipe.

I need something like a fish tank water filter thing that can constantly pour water into the pan while the unit is on and off, so the nasty water can always flow out...

Correct me if I'm wrong, but it appears a good portion of the air handler actually goes into the ceiling or duct. If that's so, it would be impossible to do any kind of repair work on this unit, such as changing relays, testing heat strips, replacing the blower motor, etc. Please tell me I'm wrong.

Correct me if I'm wrong, but it appears a good portion of the air handler actually goes into the ceiling or duct. If that's so, it would be impossible to do any kind of repair work on this unit, such as changing relays, testing heat strips, replacing the blower motor, etc. Please tell me I'm wrong.


You are absolutely right. The entire top plenum of the unit is connected to ducts (which are crappy and leak a lot). The ducts are touching the ceiling, so the unit cannot be moved at all.

I'm at a loss. The best solution is to rip everything out and start over. How did this ever pass inspection?

Apartment guys dont make inspections, they never clean the AC units unless you bug them, and they could care less about how crappy or poorly designed the unit is...

It is up to me to at least do something to get rid of the smell. The rust isn't what bothers me, it's the smell it makes.

Since starting over is not an option, and the maintenance staff doesn't know or care about fixing it, you may have to rig up some kind of small pump. You mentioned fish tank filter, maybe that's the way to go for now as a temporary fix. I can't believe I said that.

By inspection, I was refering to the city building department. Someone had to sign off on that install when the place was built. I can only wonder what happened.