Irrigation Pump Pressure Switch

mdshunk

I was servicing a failed irrigation pump today, which was mounted in a pump house. The pressure switch was the type with the manual cut-in lever. Is this type absolutely necessary on an irrigation pump that is mounted essentially outdoors? I thought that these manual cut-in levers were to keep a house from flooding if a pipe burst indoors and the pressure suddenly droppped.

CE1

MD
The manual cut-lever is there to prevent motor damage if the well runs dry due to some kind of leak/brake in the water line somewhere. I have seen a stuck toilet fill drain fail and drained the a well of all the water plus burnt out the pump motor. The manual cut out is a very good thing to have.

mdshunk

This pump is in a sippy hole of a very large creek. No chance of it pumping dry. I never acutally knew that the manual cut-in lever was to protect the pump, but it makes perfect sense.

K2

I just googled and found a maintained manual cut-out and a momentary manual cut in. Could one of you guys explain how it would work and what i might need. I have a piston pump for watering the lawn. I've been concerned about flooding the basement and burning the piston leathers. I've been hitting the disconnect after each use which can occasionally cause the pump to loose prime. Sounds like one of these switches will save me some trouble and allow me to go to a timer. Thanks.

CE1

There are some more sophisticated switches for commercial and industrial purposes. I real common one is an inline flow switch which is connected to the pumping control circuit. So if there is no flow do to some reason another pump comes on and all kinds of alarms, lights, e-mails, pages, etc, alert people that there is a problem. There are some really very expensive pumps out there that you absolutely do not want to run dry and these “Run-Dry” prevention switches help avoid expensive repairs. This also applies to critical pumping applications that require a constant flow and pressure.

mdshunk

With the momentary manual cut-in, the pressure switch has an additional lever on the side. If the pressure in the line or tank drops much below the automatic cut-in, the pump will shut down. You have to manually hold the momentary manual cut-in lever down until the pressure builds back up on the gauge so that automatic operation will resume. If pressure doesn't build back up, then you can investigate what is causing the low pressure issue. Empty well/cistern? Pipe break? Failed pump? etc.

K2

So I guess what i would need is an auto cut-out that responds to no flow or zero pressure. Is there something on the "reasonable price" market that can do this??

CE1

Best practice for pump pressure control is a switch that has a upper cutout level of say 50 psi and a lower cut in of say 30 psi. This way there is an operating pressure of 30 to 50 psi. There are pump switches that have a manual lever that turns off the pump if the the pressure falls below what the normal operating pressure range is.So if the pump is running and the psi falls below 30 psi to say 20 psi the switch will manually lock out the pump control. This way there is an indication that there is a problem and something need to be done.

Square D makes both types of these pump controls and the one with the manual lockout is well worth the little extra money.

CE1

HD has them I think.

check this out:

http://www.amazon.com/Square-FSG2J24...5?ie=UTF8&s=hi

K2

Thanks, I'll check the depot. I do have the normal 30/50 switch. I don't have to worry about it untill May.

POOLMANinCT

Always a chance of loosing prime, vibrations (causing influent side air-leak) , power outages, damage by to infuent line by fencers/
landscaper etc, the list goes on.