"Karl Townsend" fired this volley in
anews.com:

The foot valve in the bottom of my well is starting to leak water
again. Third time in 22 years. Its a 5 hp. unit 220 foot down. I
read
a while ago that I should have two check valves installed for this
application. One at the top of the well in addition to the bottom
one.

OK, I'm ordering parts to install the second check valve.

I can see the next issue, I'm going to get a burp of air every time
the pump starts. Anybody know of a device to separate this air shot
from the water in the line?

Karl




Way worse than that, Karl. If you install a TOP checkvalve in any
well deeper than 32ft, you're going to get a whale of a waterhammer
when that moving column hits your plumbing at vacuum-accerated speed.

Without the top check, the water will only come as fast as the pump
might normally eject it from x-feet deep. WITH the valve, there will
be a column of partial vacuum assisting the pump. The water will
probably be moving pretty fast when it hits the Ell-fitting at the top
of your wellhead.

LLoyd