Using Check Valve to plug lines?

[LFreed]

A previous pool person closed our pool last year using two of these check valves to plug our lower return lines. The up-side is they are easy to blow the lines - just attach it and pump air through it. It shuts off the back-flow by itself.

I'm a little leery of using them without knowing for sure if they'll hold up to the rigors of a Maryland mid-winter cold-snap. They did work last year, but I don't want to assume that means they'll always work.

Anyone ever use these instead of rubber plugs?

 

[JoyfulNoise]

Well, if it worked last year then I suppose it can work again this year. As long as the check valve seal looks to be in good shape and the internal spring isn't corroded or anything like that, it should work fine. I would definitely replace the teflon tape on the threads though.

 

[JVTrain]

I'd agree here. There are also plugs sold for winterizing called "duck plugs." Winter Duck Plug (fits 1-1/2" Threads): Anderson Manufacturing Company, Inc.

I'd trust a standard PVC check valve or a solid expandable plug more than I would these duck plugs. I assume by "lower returns" you mean that they will remain underwater after closing? Verify they still work and you should be fine.

 

[samt]

Those would prevent me from ever being able to blow out the main drain and create an air lock.

 

[ship of fools]

I used the duck plug with no issue. I only used it on the last return.

There isn't much pressure on them from the small amount of water they are holding back. If they were down 10' i would be more concerned.