20/40 or 30/50??? pump protection HELP

[loudhornsrule]

My well will produce about 7 gpm . Anything more than that is asking for trouble. 18' to static water 22' more feet to bottom of well and pump. 40' total length of casing( 6'' casing w 12'' borehole)Also 20 gallon pressure tank. Im scared I am going to run my well dry and burn my pump up.(sometimes we water 12-24 hours!) I am going to replace my pressure switch w/ one that has pump protection. I value all you guys input, so what pressure switch would you go with? I only water the yard with this well(alot). thanks

 

[Valveman]

20/40, 30/50, 40/60 is all the same switch, just adjusted differently. The main thing is that your pump doesn't cycle on and off while just using 7 GPM. Even a 7 GPM pump will try to pump 10 GPM when the pressure and depth is low. If you restrict your sprinklers to 7 GPM, the pump may cycle on and off continuously. If you put a 7 GPM restrictor before the pressure tank, it won't cycle while you are using 7 GPM but, it will cycle if you use less than 7 GPM.

You have two problems. One is that you can't use more than 7 GPM or the well will pump dry. Two is that you can't let the pump cycle while you are only using 7 GPM.

 

[Sponsor]

 

[loudhornsrule]

Valveman, I have a 10 gpm pump, but if I only pull about 7gpm usually I dont suck air. Sometimes when I am not looking my kids will open up a couple of hoses(full blast) up front away from me, and I can run out of water.Just wanted something to shut it down when I am at work. thanks

 

[Valveman]

The low pressure cut off switch or a Cycle Sensor will shut the well down when it runs dry. However, if you have a 10 GPM pump and you can only use 7 GPM, the pump must be cycling on and off while you do this. This will cause the pump to be destroyed and shut itself down when the overloads trip. Again, two different problems. Don’t let the pump run dry but, don’t let the pump cycle on and off by using little enough water to keep from pumping the well dry.