Who knows plumbing? What is this thing?

[dbrock63]

[ATTACH]553876[/ATTACH]

This is 1 of 2 of the bathroom sinks with this black drain line connecting to it. I have a two story house but we don't use the bath room upstairs. The A/C drains outside so this black hose is not an A/C drain pan line. The bathroom sink keeps backing up and I think it has something to do with this black line or the slime coming from it. This same black hose is connected to both my master bath and the shared girls bathroom so it is not the washing machine drain line. Just a month ago I unhooked the trap and it had massive slime (no hair) that I removed and the sink worked fine. Now it is backing up even when we are not using it.

Where or what is the black hose connected to? Since no upstairs shower or toilet is being used, where could fairly clean water come from that would back water up in the sink. If it were the sewer line the tub next to the sink would have water backing up in the tub before the sink at waist level would. I have never had a house with this type of hose merged into the bathroom sink. Any thoughts from the "Green Screen"?

[TXhunter77]

That is the primary drain for your A/C

[Cabela]

Primary line for your ac. The one that drains out is the secondary. Line needs to be blown out

[47]

Unless you have a garbage disposal or dishwasher in your bathrooms.... it's A/C

[dbrock63]

I have 2 a/c so it is the primary drain for both. I did not know there where primary and secondary drain lines. How do you blow them out? Is there a problem other than the lines being clogged if the a/c is producing this much condensation that it backs the sink up almost to the top?

[Cabela]

I have 2 a/c so it is the primary drain for both. I did not know there where primary and secondary drain lines. How do you blow them out? Is there a problem other than the lines being clogged if the a/c is producing this much condensation that it backs the sink up almost to the top?

Check all your sinks. Should have 1 for each ac

[Cabela]

I have 2 a/c so it is the primary drain for both. I did not know there where primary and secondary drain lines. How do you blow them out? Is there a problem other than the lines being clogged if the a/c is producing this much condensation that it backs the sink up almost to the top?

If the sink is backing up the ptrap is prob clogged and needs to be cleared out. If the secondary is dripping outside the primary needs to be blown out sorry. High pressure nitrogen. If you do it yourself be careful you crack the line then you'll have a leak as well.

[DBLHKUP]

Dishwasher overflow into p-trap

[bowhntrmatt]

It's a primary ac drain. Have an ac guy out and should be a quick cheap fix

[jerp]

I went up in the attic and pulled apart a pvc joint between the ac and the main drain. I shot compressed air down the pvc and a bunch of nasty fungus - looked like rotten mushrooms - flew out the other end. Really gross. AC guy told me to pour a small amount of bleach through that drain several times a year to prevent the build up

[Hunter75]

x2 on the bleach trick. This thread just reminded me I need to do mine.

[pappabear]

x2 on the bleach trick. This thread just reminded me I need to do mine.

X2

[dbrock63]

The "Green Screen" saved me again! Yes, I do have a drain line on both sinks coming from each of the 2 A/C units (but you guys knew that). Yes, it was the P-Trap that was clogged again after only 3 months since last time I pulled the P-Trap out and cleaned it.

What in the hell is that slime coming from the A/C line? Whitest/light gray slime? I will pour bleach down the lines to help avoid the problem.

Thanks again "Green Screen" for saving me from a repair bill! Plumbing skills and bow hunting skills - Double Score!!

[bowhntrmatt]

That slime is actually living organisms in your air that get caught in the condensate and flow into the drain. That trap is cool,dark,and wet. Perfect place for that stuff to grow. Bleach works well. Just be sure to dilute it about 1 part bleach with 10 parts water. If poured in straight it can eat certain brands of PVC glue and you will end up with a drain that is no longer glued together.

[Todd-ty729]

It is a small drain from your potty!

Don't drink the water!