We live in a rural area. Most people send the drain water from the washing machine out to their septic tank or a french drain.
Our problem: when our washing machine drains a second time in a cycle - the waste water backs up out of the stand pipe.
The stand pipe is 2" in diameter, reduces at a 90 degree angle to 1 1/2" - 2' below the washer.
Then it's 1 1/2" in diameter out to the yard for about 50'.
The washing machine is vented in common with the toilet, sink, bathtub.
Any help is appreciated. I'm thumped.

So your washing machine is drained to the septic tank, correct? The problem could just be that reduction to 1.5" drain pipe. Most washers need a full 2' pipe todrain properly due to more efficient motors.

Hi there... seems to me that you probably have a dry well that is clogged up with soap, lint and the other type stuff OR the pipe itself is clogged maybe 30-40 feet out OR the pipe itself may be broken/collapsed outside... again at a reasonable distance from the house... because as you said, drains good first cycle, but second cycle is the issue... seems to be a volume/distance issue that could be any of the above. I suggest either renting a snake and seeing what you pull out of the drain line or calling a professional drain cleaning company to further investigate the issue. Good luck!



IF my answer helped please click "rate this answer!" button below... thank you!

I would still expect a 1.5" drain to be an issue with most washing machines. Your first draining, They all drain at least twice, is a mix of water a suds. The second draining is the rinse cycle and it nearly all water.

Are we getting all mixed up with OD, ID and Nominal Pipe size? A Schedule 40 1.5" pipe is nearly 2" in OD.

Massplumber, you stated your view and I stated an opposing view, period. I did not check your answer as inaccurate but apparently you believe "Inaccurate" can also mean did not agree with me. I handed the reddie back to you, I think it is the first one I have given out in a year.

Well, wait until he sees the next code revision, Ball.

The next edition of the NPC is going to require a 3" drain, trap and trap-arm for clothes washers-- I should know, I read the White Paper requesting the amendment as well as the submittals of those endorsing the amendment.

No kidding, 3", there goes about 10% of the complaints homewoners have given us. Got anything else new in the pipeline? I just started the install of a tankless water heater and the manual is way tougher than code.

No kidding, 3", there goes about 10% of the complaints homewoners have given us. Got anything else new in the pipeline?? I just started the install of a tankless water heater and the manual is way tougher than code.

If you aren't finished and signed off by the time of the next code revision (2009) the rule regarding 18" of copper tubing immediately upstream and downstream of the inlet and outlet of a H/W Tank is going to be extended to include tankless heaters.

But you'll be finished deciphering the 'destructions' for the current installation before 2009, right? :D

I hope. Still trying to get an 8" hole through a 8" concrete wall. Actuall, now that I think of it, I will be meeting the 2009 code. I must be visionary.

I hope. Still trying to get an 8" hole through a 8" concrete wall. Actuall, now that I think of it, I will be meeting the 2009 code. I must be visionary.

Spend the money and have a coring service come out and core the hole -- It'll be a lot easier to seal when your finished labor wise than the alternative.

Thanks everyone. Clogged or 2" pipe seem to be the answers not the 90 degree angles that I mentioned. I appreciate the quick replies that addressed my problem.

massplumber2008 disagrees: I am afraid that the national plumbing code only requires a 1.5" discharge pipe, trap and vent for all residential washing machines... I figure this system worked for years and is now only becoming difficult to use.
Ahhh! The ole," If it's code it's gotta be right" attitude. Well in this case the washer manufactures have overtaken code with a more powerful washer pump. Install a 1 1/2" trap and standpipe, but also purchase a super sized mop to mop up the backups.
Bal was dead on when he wrote," I would still expect a 1.5" drain to be an issue with most washing machines. Your first draining, They all drain at least twice, is a mix of water a suds. The second draining is the rinse cycle and it nearly all water." And yiou are dead wrong. Regards, tom