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Will this float switch idea work? Answered

I'm messing around with cheap-o solar pumping project wherein I want to pump water 75-100' from a stream (or really a shallow well next to a stream) to barrel near my fruit trees.

I wanted to install a float switch in said barrel to turn off the pump when the barrel is full, but was trying to avoid having to run wire all the way from the pump/controller/battery set-up at the stream to the barrel.

I had this idea that if I pumped water first into a 5-gal bucket mounted on a tree near the pump and raised it up above the barrel, Not only would I make the most of my pump's feeble lift (by reducing the friction it must overcome and allowing gravity to do the work), but it would also allow me to put a float switch on the bucket itself, rather than in the barrel, thus reducing the wire run significantly.

Here's a picture (not all system components represented).  Will it work?  I'm wondering if there's a physical/practical consideration that I'm missing...

Thanks for having a look!



5 years ago

Thanks Toga_Dan and Kiteman!

Toga_Dan, what you suggest is the more conventional approach, and maybe it's not worth it to try to do otherwise. I will have a relay switching the pump anyway (not shown), plus a second float switch in the well (also not shown). I do already have to run cable from the panel, which will be right around where the barrel will be, back to the controller/battery/pump (so >75'). Some of my motivation here is cost, but there was also something about running the wire back and forth that was just bugging me.

Kiteman, I've rigged a filter of sorts on the pump intake, so hopefully that'll take most of the debris out. It could still be an issue though. Good idea about laying the barrel on it's side.

One thought: If the bucket at A drains slowly, it would end up turning on an off the pump every time the water backs up, but it would eventually equal out with the water in the barrel at B, no? Maybe it's not such an issue since it'll only do that until the barrel is full.

Something like this is what I planned to use for the cable from the panel to the controller, by the way, unless anyone can recommend something cheaper that'll do the job. 

Thanks again for the comments!

when there's only a foot or 2 of water pressure, a 75 foot pipe may have a lot of resistance to flow.

i suggest 75 ft of cheap, lightweight wire- float valve at B. small current through this wire controls a relay to power the pump

It looks good to me.

My only concern would be blockages: debris from the stream getting into the pump, and (in the long term) I might worry about things growing in the pipe and restricting the flow.

You could reduce the pumping-height by laying barrel B on its side, as long as it has suitable fixtures and fittings.