Washer Drain/Cheater air pipe?

[Anna]

I need to connect into my existing plumbing to add a clothes washer drain. Hopefully this lay out explains what I need. I need to know if I will be putting in P-trap in right location? And do I need to put in a cheater air pipe to eliminate backup or drain off of P-trap, because of kitchen sink being high elevation than washer, or other cause?? If I need cheater air pipe where do I place it? I only plan on putting in a pipe connection to put my washer drain into, do not want to put in a wash tub as I do not have the space available. Any advice is appreciated. Thanks in advance.

Kitchen sink | | |_____over 20 feet_______ | |Down 2feet |______over 8feet ??want to connet here

I want to connect a clothes washer drain pipe here ?? into the pipe of eight feet run Then the pipe continues to run over 2 feet

| |drain from upstairs bathroom | ?? ___over 2feet__|___over 6feet____ | O Then drops down into main P

[Speedy Jim]

The pic wasn't entirely clear (it's hard to show in ASCII), but yes, you will need *some* kind of vent to prevent siphoning of the water in the new P trap.

When you cut into the main drain, insert a "WYE" fitting or a "TEE-WYE". The inlet should be 2" size. Run the 2" pipe 5 feet over to washer location.

VENT\\/ | TEE|-----U----/ Washer Inlet | P-Trap /------------------------|

----/-----< Main Drain WYE

Whether you are permitted to use a mechanical (cheater) vent or have to run a vent line to roof is up to your inspector. Mechanical vents are like:

Good article: Jim