The sump basin is next to a drain that is 20 inches deep lower than basin top floor level. It is an easy backup siphon, however; How can i get it to repeat prime w/o attention aft it has shot it wad? Check valves etc??? I spose a battery vacuum but prefer totally PASSIVE. Any experience? Thanks
PS I am about to set up my test lab. Ha Ha.

If you have a "spring loaded" check valve AND the spring is just strong enough to almost support the column of water in the pipe, (just below the water level in the sump, and the inverted "U" would have to be below the water level also in order to fill the pipe), the the pipe would fill with water, the check would open, the siphon would start, and hold the check open until the flow stopped. At which point the check would close and start the operation over again.

If a basement floor sump pit is allowed to fill near full, does it put bad strain strain on the floor slab?

when my son first bought his house he had a terrible water problem. it was not like that before but they had a new septic system put in with a raised leech field which quite obviously changed the water table around his ranch house.
anyway I said lets dig a hole and put in a pump.
so I got what we needed and proceeded to drill a small hole in his slab. the water shot up about 2-3 inches like a drinking fountain.
I went outside and cut a small branch off a tree and pounded the round stick into the hole. I smiled and said "we'll dig when the dry season is here"
to answer your question, his slab had a heck of a lot more pressure under it and nothing happened to it.

I kinda thought so about the slab strength, or else everyone who had water in basement would have heaved slabs.
Thanks for the important bit of experience from your side.

My purpose will be to get a siphon that will have the inverted U about an inch above the slab. The system will feed on the basin side about half way up like 10 inches up the basin pit and then drain substantially lower.(20 inches) My trick will be to ensure that I can depend on restart of siphon; preferably automatically.(Given my elevated inverted U) situation. I do imagine perhaps a battery powered vacuum will assist in re-prime if my imagination cannot find a way to make it go by itself. At least if needed, intermittent battery backup power would last for days. If I am going to be a Rube Goldberg, then I'd like to do so with good style.

Somebody out there is a better "Rube" than I am. I shall overcome I do believe.

Thanks for the help to both of you gentlemen HJ and Packy and; scholars of the art of hydraulics.

Ricker



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