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
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?

And if so - what's the best location to install it. The PVC exhaust that
the washer drains into has a vertical part that then flows into a
horizontal part. Is better to install the check valve is far down the
stream as possible? or the other way around? or six of one?

Many thanks in advance!

Aaron