Two Sump Pumps Sharing a Pipe

[lagman]

All,

Last year, I installed a second sump pump above my primary pump using the design in the picture below. I used two brand new independent check valves. Everything worked great last year, but now that my pump has started running again this year, I'm hearing water drip out of the bottom of the backup pump. So for some reason the second check valve isn't doing its job. Am I just forced to concede that in this type of setup the second check valve isn't always going to be completely water tight? Any advice you can give me on the design pictured below would be great.



Thanks!
Dan

[cacher_chick]

Much of the problem is likely due to the quality of the valve. If the rubber deteriorated or a tiny bit of debris has gotten on the flapper or it's sealing surface preventing it from closing properly, it is going to leak. I have had good luck with A.Y. McDonald check valves.