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washer backflow

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Nov 01, 2013, 11:58 AM
washer backflow
I recently moved into a new house.
The laundry room is adjacent to the bathroom with the bathroom sink on the wall closest to the laundry room.
When doing laundry and the washer is draining, right before the spin cycle, the water backs up into the bathroom sink and drenches the bathroom floor.
If I use the small cycle in the washer it helps a little, but it's still something I would like to fix. When looking at the drain pipes, it appears that the washer and bathroom sink use the same drain.
How big of a problem is this to fix? Is it something I can do myself?
Nov 01, 2013, 12:36 PM
Is this a new house...or new to you? Often times this will occur when the stand pipe drain line (for the washer) is partially clogged near the bottom with lint or debris from the wash loads. So it cannot take the water as fast, and can back up into an adjacent drain like a laundry sink or your lav.

Might try running a flexible snake line down the stand pipe, to see if it can be cleared?
Nov 01, 2013, 12:56 PM
It's not a brand new house, just new to me.
Although one of the improvements listed when we bought it was that bathroom and laundry room were renovated.
So I guess it's possible that the pipes are newer?
Nov 01, 2013, 01:51 PM
New drain lines are most often now pvc, but they may also have an old trap below the floor that was possibly cast iron? (if the home is older). This is more naturally rough and can catch debris like lint from towels and heavy cotton, as it drains out the washer. We have had to clean ours every 12-15 years or so.

Not to say you may still have a possible issue with the plumbing hookup with the lav & washer drain, but I would still check the line that drains the washer, as it is easy to eliminate if there is an obstruction.
Nov 01, 2013, 03:15 PM
the word renovated scares me..and should scare any and all potential home owners...who did the reno? diy? joe blow and his 2 cousins?
your drain naint hooked up need to hire a plumber to put a camera down ther and see whats what
2 reasons a washer backs up into a sink
the main line is root bound
or it the drain from the washer is hooked up to close to the inlet of the sink
there is a provision in the code called "suds relief" witch means the tie in to the main for a washer SHALL be no closer to another tie in by 5'
so that,,,suds wont back up and piss off the home owner....$400 bucks for a camera guy
Nov 01, 2013, 03:36 PM
Closer than 5 ft can work, however it is probably not to code, as Frodo mentioned.
Our '58 ranch has a utility sink slightly less than 3ft from the washer stand pipe, and it drains into the stand pipe from the side. The only time wash water has backed up into the sink was during those 10 plus years between clean out of lint and such in the drain.
Nov 01, 2013, 06:58 PM
The best fix is to make your drain lines work for the volume of drain water from the washer - as outlined in other posts above. This is also the hardest and most expensive fix.

However, I've seen quite a few houses washer drain set-up were working fine until a new washer was installed. Many of the newer machines (and by newer, over the last ten years or so) drain faster than older models. A simple fix is to install a small restrictor in the end of the washers drain tube. This can be as simple as a short piece of pipe that fits inside the stock drain pipe and is clamped in place.

Nov 02, 2013, 11:18 AM
thank you all for the ideas. I will have a busy weekend trying to get this taken care of.
Nov 02, 2013, 05:17 PM
Is the drain for the washer 2"?
A picture where it ties into the sink drain may help.