My family moved to our current house in May 2010. The house (late 1970's) has a basement with two sump pump pits - one was original construction and the other a french drain system (I think) leading to a pit added in 1990. We use the "added" french drain system as our primary pump and the secondary sump was unplugged when we moved in (we left it unplugged since there is no good place for it to drain).
The primary pump was replaced with a Little Giant 4/10hp w/integrated diaphragm switch (8-CIA) along with an Zoeller Aquanot II backup system in June 2010 after a power failure flooded the basement. This pit is active! The pump will cycle on for about 20s and then be off for about 1-2 minutes before filling up and pumping again (FYI - check valves were also replaced along with the pumps).
In September 2011, the switch on the Little Giant failed. I was prepared for this and had a replacement switch on hand to fix the problem. I am really in need of a switch that can hold up to my 262 thousand cycles per year! I've read in these forums (and others) that professionals recommended SJE Vertical Master switches and generally dislike diaphragm and electronic switches. Have any of the experts out there used the LevelGuard switch (http://www.levelguardproducts.com/sump/index.php)? The manufacturer rates it for 1.5 million cycles with a 5 year warranty.
My plumper recommended yearly pump+switch replacement - I just can't justify $200/year for a new pump.
Thanks in advance!
So based on a sample of one your diaphragm switch lasted approx 330k cycles. The original Wayne pump (Lowes used to carry WaterAce but switched to Wayne) had a diaphragm switch sort of piggybacked on it. Coincidentally, that pump lasted approx 15 months but failed due to the pump or motor seizing. As it also carried a lifetime warranty, I was able to exchange it. By that time the manufacturer had redesigned it to use a vertical float switch with a very short on-off differential. Replaced 2 in 8 months since.
So the diaphragm switch was still functional after I am estimating 125k. The turn on level did drift a little upward with time. Not a major issue.
I see ballvalve suggested a heavy duty relay. I have also considered wiring two external switches in parallel at different heights. If you have the physical space to do that, it gives the advantage should a float stick with debris or mechanically jam. I have also learned to test the backup once a week.
We have been in this house 10 years. Think I have replaced the pump 7 times.