Yi Jin wrote:

I replaced my sump pump a while back. I put a home depot
check valve between pipes while doing it.

The sump pump works fine. Then I read the sump manual again,
and it said I should drill a 1/8" hole on the pipe just above
the sump connection, to prevent air lock. So I did it.

Now whenever the water level in the pit is lower than that
hole, the hole is ejecting a strong stram of water, and noise
is noticeable. Is it really necessary to have a hole there?

What is the air lock anyway? I can't find the denifinition
from my DIY books.

YJ

For more info on "air lock" and the necessity of that hole in the
discharge pipe, do a google search:

http://www.google.com/search?q=%22su...%22air+lock%22