Draining washer into septic

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Ewhitaker0020

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Is it okay to drain my washing machine into my septic tank? I'm adding a washing machine into a house I'm moving into. It currently has no washer dryer hookups or drains or anything. The property has a septic tank on it instead of city sewer. Also the drain line I'll be tapping into is a 1 1/2 inch like I believe. Is that big enough?
 
Since the washing machine water doesn't have any solids in it will it just leech out of the septic tank fairly quickly? Also the drain line will be ran out in the open, meaning not under my house but also not in direct sunlight or anything, will I have a problem with this drain line freezing up in winter? I'm moving into my in-laws spare apartment and I have limited options when I'm running this drain.
 
It's fine. The current code calls for 2", but 1 1/2" was the norm for many many years

You also have to take into consideration the newer washing machines having a higher discharge rate. Just monitor drainage to make sure the system can take it if not upgrading.
 
Where exactly do you plan on running it? Is it an un heated space?

Yeah unfortunately it runs under the house but is briefly running just beside the house. It's still covered from the elements but it's not in a heated space at all.
 
You also have to take into consideration the newer washing machines having a higher discharge rate. Just monitor drainage to make sure the system can take it if not upgrading.

How much of a slope does the line have to be on? If I sloped it more would that help the drainage?
 
Also, should I make the new drain a 2" then reduce it to 1-1/2" when I get to the rest of the line?
 
My washing machine has run to my septic for years. Only recommendation I have is try to avoid bleaches and other chemicals in your laundry. They upset the happy bacteria in your septic tank. Keep up on your rid x or put yeast down the drain on occasion.
 
My washing machine has run to my septic for years. Only recommendation I have is try to avoid bleaches and other chemicals in your laundry. They upset the happy bacteria in your septic tank. Keep up on your rid x or put yeast down the drain on occasion.

The septic system we'll be using hasn't been used in about 8 years. It's still in great shape structurally but is there anything we need to do to it to get it ready for use again?
 
Only real way to tell us use it. If it works you are good to go. If it doesn't drain then you are looking into leach field work.
 
Do I need to put a trap on the washer drain? if so how far below the drain? Also do I need to put in a vent in for the washer? The closest vent is like 15 feet away.
 
Yes. You need a P-trap. And a standpipe P-trap needs to be above the floor.

To quote a code page I just googled:
The Uniform Plumbing Code (804.1) requires clothes washer standpipes to extend at least 18 inches above the trap, but not more than 30 inches.

The pluming portion of the Residential Code (P2706.2), allows for a minimum height of 18 inches above the trap with a maximum height of 42 inches.

The International Plumbing Code (406.2) has no such language for the minimum or maximum length.

The reason you should not reduce the size of the drain pipe is because it is a code violation. You may go larger by one pipe size, but you may not go smaller. Going smaller can create somewhat of a bottleneck when large quantities of water are draining.

The developed length of the trap arm can't be less than two pipe diameters nor more than 5ft before it vents.

If you don't know what plumbing code your state uses, you can look it up in the Plumbing Code By State thread.
2005-11-24_UPC_laundry_standpipe_w550.JPG


The slope for 2" pipe generally needs to be 1/4" per ft.

I think Frodo can tell you more about UPC. My area has its own plumbing code based on IPC.
 
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I live in Kentucky so I'm using ipc it looks like. In that picture you showed it has the vent going out the roof. Can I run the vent up then out the side wall? It's covered and won't get any moisture in it. I'll be entering another drain coming from the kitchen sink about 20 feet away. Should I tee straight into this pipe? I'll try to get some pictures later tonight
 
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