On Nov 20, 10:18*am, Andy wrote:
On Nov 20, 9:10 am, "Joe J" wrote:





In the same crock I have two sump pumps on two separate breakers. *The
primary pump has a check valve installed and it drains into a underground
pipe that runs to a sewer. *The backup pump float is set a little higher and
turns on if the primary doesn't. *One and a half inch pvc pipe that rises
about 8 ft and does a 90 degree turn before heading outside and draining
onto the lawn and it has no check valve.

So here are the questions...Is there a valid reason for not having a check
valve on the backup? *I had a failure on the primary pump and it seemed half
the crock was refilled by the remnants in the pipe draining back after the
backup pump shut off.

Is there a standard height a check valve should be installed and wouldn't it
make sense to install one on the backup pump?

This was the arrangement when we bought the house in March and I only
noticed this after the primary failed. *Actually, the pump didn't fail, the
float switch did. *$30 for a replacement.

Andy comments:

* I would think that if the water level get high enough to fill the
second
pump (as a result of the higher float switch), that a check valve
wouldn't
be necessary.....
` * The check balve is merely to keep the pump primed,

Sump pumps are all self-priming out of necessity. And
a check valve will not keep it primed anyway. The water
between the pump and the valve drains back into the
sump pit. The valve is there to keept the rest of the water,
which could be substantial depending on how the piping
is run, from draining back into the pit. If it does, the pump
is just re-pumping that same amount of water that drains
back each cycle.




and if the pump
is flooded, a check shouldn't be necessary unless it clicks on before
the
water level is high enough...... *HOWEVER, that being said, what is
the
nature of the second sump pump.?? *Is it a submersible, or is it a
pump
that is mounted above the water level ??

How many sump pumps have you seen that are mounted
above the water level? Every single one I've ever seen
sits in the sump pump pit, in the water.



That would be a problem....
and
I would use a check valve....

* * I will read with interest the advice given here by others. *Lots
of good
info to be gleanded from this group...

* * * * * * * * * * * * * * *Andy in Eureka, Texas * P.E.- Hide quoted text -

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