"Steve Barker" wrote in message
...
On 11/20/2011 8:36 AM, Colbyt wrote:
wrote in message
...
Andy comments:

Joe, I'm sorry, but I really don't understand.. If both pumps are
submersible, --- by that I mean the type that, when operational, is
partially submerged in the sump, I don't see the need for a check
valve in either.... As long as the float switches are above the pump
levels, the pump will be flooded.. and primed.... Water flowing back
down a discharge pipe will flow out to the ambient water level, which,
if the pump is still submerged, shouldn't matter.....

However, if your "primary" pump didn't work, you should get it
fixed.... As a suggestion, the problem may actually be in the
float switch (sold at Home Depot as a separate item for about $30
USD)..
and is easy to replace..... generally.... The float switch fails more
than the pump does, in my experience....... which may not be as
great on this issue as other posters..

I like the idea of a backup..... especially if a small flood will
cause you serious difficulty or loss... But I'd have both systems
working ..... That's just me, tho....And I really like the "separate
breaker" approach...

Andy in Eureka, Texas


Andy

The only purpose of a check valve on a submersible pump is to prevent the
backflow which can cause the pump to cycle repeatedly.

The water in the pipe refills the basin prematurely. The pump kicks on,
shuts off and the whole process repeats again. Over time this can cause
premature pump failure. I once watched one with a small basin pump the
same
water every 2 minutes. I added a check valve that very day.

For Joe: Add a check valve. Be sure to read the instructions. You need
to
drill a 1/4" hole in the pipe near where it connects to the pump to allow
the water between the pump and the valve to drain.



the 1/4" hole is a wives tale. Not necessary.

Actually the hole is built into the pump on a Zoller pump. It is smaller
than 1/4" , but they seem to think it is important. When I was having a
problem the first thing they asked me was if the hole was plugged.

R


--
Steve Barker
remove the "not" from my address to email