Low Pressure Issue - sprinklers/well

[Randy Utecht]

I recently purchased a home with a 20 year old pump (submersible @ 50' - 1/2 hp), pressure tank and sprinkler system. Neighbors on both sides have the same set up (they all installed together) with no issues. When I am not running sprinklers, system seems to run fine. Great pressure in the house, tank fills and pump cuts out at about 45 and kicks on at about 25. However when i start up my sprinkler system, no matter what zone I start on, they start fine with good pressure for about 1 min., then the pressure drops off and I get about 2 ft of spray. Pressure gauge drops to about 17, pump runs continuously and tank does not fill until I shut down sprinkler system. 12 zones, with 4 heads on each zone. Talked to neighbors and previous owner and they all said it ran fine last summer. What could be causing my issue?

 

[Valveman]

Either you have a leak in the line, the sprinkler nozzles are washed out or gone, or the pump is not putting out as much as it should. Do a bucket test to see how much water the pump is putting out at 17 PSI.