On Wed, 21 Oct 2009 06:46:01 -0700 (PDT), wrote:

On Oct 21, 8:43Â*am, Jim Elbrecht wrote:
On Wed, 21 Oct 2009 05:27:19 -0700 (PDT), wrote:
On Oct 21, 7:59Â*am, Jim Elbrecht wrote:
Aaron Fude wrote:
Hi,

My washer is basically at the same level as the main stack (or whatever
its horizontal equivalent). So there is not sufficient elevation to have
Â* a p-trap on the exhaust (take my word for it - I just can't do it).

So I bought a check valve at HD. I think it's intended for a sump pump.
Will it solve my problem?

No - if it is a check valve, it will catch lint, clog & never shut
properly after about a week of use.

This is what you want-http://www.hardwareandtools.com/invt/6833156

HD carries them as a "cheater vent" Â* Â*- Â* Put it on the top of the
pipe that your washer drains into- and sani-T the drain hose. [there
should be directions showing installations in the package]

Jim

That solves the problem of not being able to have a vent pipe on the
drain where it is located and works with a P trap. Â*It does not
eliminate the need for a P trap, which is what the stated problem is.

I am not a plumber-- and I know some codes don't allow them. Â* But
they work fine as a vent, and don't allow sewer gas into the house.
[the latter being the purpose of the p-trap, right?]

They work as a vent in COMBINATION with a p-trap. In an installation
with a p-trap and conventional vent pipe, the water in the p-trap
blocks the gases from coming into the house through the drain and the
vent pipe gives the gases an alternate low pressure exit out the
roof. The device you recommended, commonly called an air admittance
valve, is used where you can't provide a nearby vent pipe, like a
kitchen island sink. It allows air in, to prevent a vacuum from
forming and allowing water to flow normally. It will not allow waste
gases to come out through the valve in the reverse direction. But
the gases will still flow right out of the drain if there is no p-trap
filled with water. Also, the air admittance valve depends on there
being some other actual vent pipe in the system.



Big advantage of the "cheater" is it keeps the drain from siphoning
the trap dry.






He says there is not sufficient elevation for a P trap, for which I
think we need more explanation..

I agree here- a picture of the setup would probably elicit a 1/2 dozen
ways to attack the problem.


Yes, since the typical washer can pump probably as high as the
ceiling, it would seem a p-trap should be able to go somewhere.




Jim- Hide quoted text -

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