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Starting Member


Wednesday, June 6th 2018, 1:57pm

Fluctuating pressure on only part of the system

I have an irrigation well with a lot of pressure. When I run
zone 1, which is farthest from the well head, the pressure on the pump reads a
steady 65 psi. Zone 2 is about the same and zone 3 drops to 50 psi, but is
steady. However, once I hit the last 4 zones, the pressure bounces around between
50 psi and 20 psi. Any idea what could cause the pressure fluctuation?


Active Member

Posts: 42

Location: Washinton


Wednesday, June 6th 2018, 8:09pm

Depending on the type of pump, it may be due to cavitation. What that is the pump's mechanical components are spinning faster than the water coming through it, creating small pockets of air.
What to do about it?
First you need to find out if the last few zones are using more water than the others, count the number of heads and make sure there isn't any leaks.
If everything checks out, sometimes this is due to the water table dropping and the amount of available water. As people on well and pump systems begin to use more and more water the water table drops. Making it harder for the pump to pull water from the ground.
If this is case, you can change out nozzle sizes on your heads, to reduce the overall GPM or Gallons Per Minute. Sometimes adjusting the "flow control" on the pump helps this as well. The flow control is a small screw on top of the pump casing that prevents water from exiting the pump. Instead the water is re-circuilated through the jet, giving it more lift. I have had limit sucess with adjust this.


New Member


Thursday, June 7th 2018, 9:30pm

I have a culinary eater system. I have one zone that is very low pressure but all my other zones have great pressure. I have replaced the valve a checked for blockage in the line. I have ran the system for several hours and have not noticed any bubbles or soft parts where my line “should run.” I say should because I am not sure exactly where the lines were ran, my system was installed by the builder and I did not get the plans. I am hoping for suggestions to finding a leak or or any other problems I might be missing. I have also checked the control valve and valve and it is fully open. Thanks in advance...

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