You are not logged in.

Dear visitor, welcome to SPRINKLER TALK FORUM - You Got Questions, We've Got Answers. If this is your first visit here, please read the Help. It explains how this page works. You must be registered before you can use all the page's features. Please use the registration form, to register here or read more information about the registration process. If you are already registered, please login here.


Starting Member


Sunday, April 10th 2016, 5:25pm

Pump looses suction

Last year I installed a new system. I have a 4" line coming from the irrigation canal 1/4 mile away with a elevation drop of about 25' feet to feed my 2 hp pump. This drop gives me about 4-6 PSI on the inlet. I have 4 stations of rain birds with maxi paws with 10- 12 heads each. The heads are feed by a 1 1/4" line to 1 " laterals then to the heads. After about 25- 30 minutes of pumping without any problems, I can hear the pump making noises ( not smooth as when water present ) the pressure drops until no water is pumped to the sprinkler heads. I will then open a valve about 100' back on the 4" line, the flow is slow a first but then it gradually increases the flow to where I then can resume operation of the pump. Its like the water stops flowing to the inlet.

I've added an air vent back along the 4" line, this hasn't solved the problem.

Do I need more air vents or a check valve.


Supreme Member

Posts: 5,352

Location: Metro NYC


Sunday, April 10th 2016, 7:18pm

Is the intake always well under water? Can you be certain there are no suction leaks?

Rate this thread