Laundry Sink Drains Slowly

Question

My washing machine drains into a basement sink, which is connected to the same pipe that handles the kitchen sink and dishwasher located upstairs. The drain has never kept up with the washing machine discharge and the sink slowly fills up as the washing machine runs. This problem is inherent to the house as the previous owners told us about it before we moved in. All other drains in the house have no issues.
I'm curious as to why this sink in particular has always drained slow. There are 4 elbows between the trap and the sewer pipe, which is a 2" pipe that goes into a 3" pipe in the floor. There appears to be a separate pipe for the basement sink's vent. Looking into a cleanout reveals the inside of the pipe is lined with thick black sludge, which I assume is from the kitchen sink? If the basement sink is filled with water and then released, water can be heard rushing through the pipes for a few seconds, then it goes silent and the flow slows down. I have tried a plunger, drain cleaner, and a snake, all of which had minimal effect. Is there something building up in the pipes that makes it drain slow or is there a design flaw in the plumbing?

HoneyDo · Answer

Snaking is a good method to clear a drain but it won't remove the black sludge you mentioned that coats the inside of your drain pipes.
That gunk builds up over time and keeps narrowing the inside diameter of the drain until it clogs. Sometimes very good liquid drain cleaners will help. I've used Hair and Grease drain cleaner with good success that you can pick up at most home stores.
However, the best approach when the problem becomes chronic is to bring in professional grade equipment that scours the interior of the drain and thoroughly cleans it. There are many good companies that can get the job done for you. If you like the DIY route and want to save a few dollars you can also rent the equipment. Make sure that you're getting equipment that uses rotors so you're not just clearing the center of the pipe but also the pipe walls.

Edwin Lozada · Answer

I had the same problem but mine was spitting out of the drain hose but I have a septic tank I had the main and laundry room drain pipe and they did a water jet cleaning problem solve

Laundry Sink Drains Slowly

2 Answers

Add your own answers!

Ask a Question