I installed a 4 foot well head for a sprinkler system 9 months ago. I completed the sprinkler system and actually started using the pump just 3 months ago. Everything was working well, and then the pump started cycling continuously. My brother suggested we install a check valve, which we though was part of the well head. After installation, the system worked for about a month and then started cycling again. I assume the check valve has failed. Is this common, to have the fail in shallow well systems? Is there a better way to do this? I am very new to all of this and just trying to learn as I go; any help would be deeply appreciated. thanks!!!