Water overflowing from drain pipe

The problem with the new washing machines, is that they dump 20-22 gallons of water in 4-5 seconds. This amount is far more than the garden hose test will submit the drain to. Here are a number of solutions, I hope that one of these will help you.

#1 As mentioned above, you can restrict the flow of the drain pipe. I recommend a 3/4" x 6" brass nipple, or a 1/2" x 6" brass nipple, depending on your specific situation. The brass nipple will not corrode like a galvanized nipple.

#2 There is also a rubber cap that you attach to the drain pipe that fits around the drain hose tightly.

#3 Some situations might require that you have to raise your drain pipe. It is recommended that it be at least 36". This allows for gravity to assist the drain.

#4 Some situations will require that the drain pipe be increase in diameter. Older plumbing applications were installed using 1 1/2" piping. With the newer washing machine discharge volume, the 1 1/2" pipes will not support the discharge. Your drain line will need to be changed to 2". This option will be one of the more costly fixes, depending on the amount of line that needs to be changed.

#5 Some plumbing installations installed without a p-trap will need to be changed. The p-trap keeps sewer gas from coming back into the house. It also allows for a smooth transition into the drain line. Any restrictions in the drain line (i.e. ells, tees,) will cause the soap in the gray water to foam up which will cause the drain line to slowly back up.

I hope these solutinons help.

If the water is backing up from the standpipe then you obviously have a problem. The most important thing is to properly diagnose the problem. There are many factors that come into play, however. Factor #1 - Is there a clog in the line? Run a water hose in the standpipe and see if it backs up. If so, the line needs to be cleaned out with a 3/8" drain cable. Then test the performance of the washing machine. Factor #2 - Did you recently get a new washing machine? The reason I ask is because newer washing machines have a higher output than those manufactured 10 or more years ago. If the washing machine is new, and it is backing up during the spin cycle, but the machine you just replaced was draining with no problem, or you have tested the line with a water hose, then the problem is the stand pipe. The STANDPIPE is the pipe the hose sits inside to drain. When the home was built, the standpipe was sized at 1 1/2 inches to handle the output of the washing machine. The pipe and it's trap are that size until they dump into a 2" drain line which runs into a 4" drain line. THE SOLUTION is to replace the 1 1/2 standpipe and trap with a 2" standpipe and trap. The larger pipe and trap will handle the higher output of the new washer allowing easier access to the 2" drain.

I have the same problem with the washer drain overflowing as it drains the tub.  Have had a plumber run the snake, sewer and drain people come with the "big" snake to go from the house to where the city line connects, and the city out to check their side.  I am convinced that the problem lies in the amount of water being forced out of the tub and into the vertical pipe.  First, I think I will try to reduce the amount of water coming out of the washer.  If that does not work, then I will have to look into the possibility of getting a larger diameter vertical pipe,,,

I would say that the problem lies somewhere within the house plumbing. Finding it seems to be the problem. The garden hose would have more pressure than the washer. However, the volume from the washer probably is greater than that of the hose. This is because the washer hose is greater in diameter than the garden hose allowing more flow at less pressure. So much flow in fact, the problem drain lines in the house can't handle it fast enough. A work around could be to restrict the flow coming out of the the washer. You may be able to do this by clamping the end of the washer drain hose or clamping the hose in the middle somewhere. This will not hurt the pump, it will just take longer for the washer to pump out preventing a "flash flood" of your house plumbing and your floor.

The new washer machines pump to fast compared to the older ones.There is a product that solves that problem.GViivalve.com.Keeps your drain clean,no siphoning out,and no hose pop outs or overflows.Thousands in use and is proven and patented. Thanks

I have used the "nipple" successfully. I have the same issue. My home is 60+ years old. We moved in 3 years ago with a new washing machine only to see water spout from the discharge pipe from first use. First plumber created an incline on the pipe leading to city plumbing. It helped but still over-flowed. The restrictor fixed the issue. I think the real problem is city drainage and the new washing machines discharge too quickly for some home plumbing to handle. Comments above suggest they shouldn't drain too quickly and I totally agree... I am willing to pay $0.05 extra a month in electricity to cover the extra minute the pump is on.

Jeff in BC Canada

One note (Mar 2016) I'd like to add is this: We now have a NEW LG front load washer, and it regulates the discharge rate so there is no over-flow issue. I can hear the pump come on intermittently so it does a little at a time. The last washer started having main motor problems and we thought a new washer would be fewer headaches.

I am having the same problem that most of you are suffering from also. I have just removed a lot of old pipes from a suite that was in the basement next to the laundry room, and after replacing the standpipe and drain line my machine now overflows out of the standpipe. I did not install a trap but have noticed that the drain line does not have a Y-Tee but a straight Tee. I think that the straight tee is not allowing the waste water to drain away fast enough. Any thoughts on this. Thanks, Bud

I had a stubborn clogged drain pipe. It took 4 times with a 3/8 " power snake until I stopped getting calls from the tenants. The chemicals I bought were no use.

I have the same problem - exactly the same problem. Hose drains fine. I am wondering if you solved your problem? What did you do?

LarsTo here, I have exactly the same problem. We have not changed washing machines. We have not changed any plumbing. Frequently I find an overflow. I have stood and watched the complete cycle of the washing machine and noticed that the soap bubbles, aparently with water in the suds, comes right up the drain standpipe. I have done the drain cleaner thing, the hose thing, the drain in the sink thing, and only spent money and time. I have a friend who is a plumber and asked him about my problem. "Too much soap used in the load", he says. I look in the liquid soap cap and see lots of lines. I tell my wife what my friend the plumber says, and she replys; "I only used a little." Last evening it happened again, this time I look for answers on the internet. I tell my wife what others are saying and she says, "Well maybe I'm putting too many cloths in the machine". I get in deep trouble reminding her not to use as much soap as that new wasing machine that does 15 pair of jeans per load. I hope I can be teachable, maybe even a few others remain so.

I hate to dig up an old thread, but I have been having a lot of trouble with a new washer. When it drains, the water will overflow out of the standpipe. I removed the drywall around the drainpipe and have a bucket under it. I know this is not the answer, but i had to do something.
The main pipe is 2 inch, but the beginning of the drain pipe is 1.5 inch (where you put the drain hose from the washer). After a foot and a half there is a reducer that connects the 1.5 inch pipe to the 2 inch pipe, then a P trap, then horizontal for 2 feet then into the foundation. There is an air vent through the roof, and I assume that when the drain pipe goes into the foundation there is a T and the vent goes up (I have not removed that part of the wall to look, but I can).

I have two questions that I would be greatly appreciative if someone would answer ;


1. Do you think that removing the 1.5 inch section of pipe and replacing it with 2 inch pipe would fix the overflow problem? I wonder if the drain is not able to vent properly because the 1.5 inch pipe is too small now that the new washer is pumping water faster.


2. I have thought about a flow restrictor at some point in the drain. I have read, above, that some people do this, but where do you put the restrictor? Should it be placed at the end of the drain hose? or at the outlet of the pump before the hose connects? I imagine that there would be trial and error with this idea, as I would not want to restrict the flow so much that the pump housing cracks or blows a seal or something. If I put the restrictor at the end of the drain hose, what should I use and how do I attach it?


Any help would be great. I do not want to have to keep emptying my bucket after every 2 loads. The overflow is usually not that much, maybe a cup or two each load. I have used drain cleaner, but have not had the drain snaked. Many thanks in advance.

Your experiment to run the drain hose into the sink and the fact that water didn't drains immediately, shows that you have a blockage on your main drain line !!!! The garden hose running through the pipe didn't raised up the problem because of water's pressure. My recommendation - Buy an "open blockage" liquid (you can get it in all hardware stores) and use it following the instructions you have on the bottle. Good luck !!

Has anyone suggested to reduce the water flow out of the Washer? Maybe installing a restriction in the drain hose will solve the problem. The Washer Machine doesn?t have to empty in 4 or 5 Seconds. The spin cycle lasts for 4 to 5 minutes. My older model Maytag never had this problem in the 10 or 12 years we had it. As soon as we installed the new Maytag, I had to increase the height of the stand pipe, but even this didn?t correct the problem.