Air Conditioning - drain pipe

Is there anything wrong with having a 90 degree pipe that bends upward on the drain pipe coming out of the house? Will it block the pipe from draining and cause the A/C to overflow?

DLAP46, Welcome to the DIY Forums.
From a Plumbers prospective : Water seeks it's own level. If the drain has an elbow looking upwards, the water will flow back to the unit and cause an overflow. Unless there is a pump on the drain, you will have a problem. Good luck.

As long the opening is lower than the Coil, it should be ok. but only problem. if that pipe is same level all the way, be a lot of standing water, a higher chance of plugging.


Why do you want to turn it upside down?

Thanks for your helpful replies. To give more detail: The unit is in the attic and the pipe comes out of the crawl space. The elbow goes up only about 1 inch Someone once said that it should have an elbow going up so that some water is retained to keep bugs and other critters from crawling in. I guess my question is will the water coming down from the attic be enough to push the water up that 1 inch so that it will not back up and overflow or will the 1 inch uphill flow be enough to cause the pipe to back up and overflow?

It's ok, as long the air handler is up higher. I would once a year take a shop vac and suck the pipe outside to clean up any gunk that may be in the pipe.

Id for sure put just a 90o up on the end outside there. Dont glue it on just slip it on. This will keep bugs out that can stop it up . Like Jay said pull the 90o off and clean the line out once a year.

ED;)