Overpressure

[Barry]

Just installed a csv for a small tree irrigation system.  The well and pump have been working fine. Now I am getting blow out from the 75psi overpressure valve when the flow is shutoff and the pump does not shut off.  When the system is opened up to full flow (20psi downstream) I can only get 10 psi. Is it possible the CSV is clogged? I did a flush out prior to assembly. The over pressure valve is on top of the head, prior to the CSV. Any ideas?

[Cary Austin]

You should have been getting "blowoff" from the pressure relief valve from the minute you installed the CSV.  Because the pressure relief valve should not be installed prior to the CSV, only after the CSV.  Whcih CSV do you have?  It sounds like it is just set too low.  Call us and we will talk you through the setting.  800-652-0207

[Barry]

Cary,
Yep, moved the relief valve past the pressure switch and it works fine...thnx.  Next question, does the csv totally eliminate the pressure cutoff switch?  When I shut off my irrigation, the pressure guage climbs up to almost 60 psi, well above the switch setting and the pumps runs unless I shut off the power. Is there another issue here?

[Cary Austin]

Barry
Now you are having a problem with the pressure switch.  If the switch is located in the correct position (close to the pressure tank), and see's the same pressure as the gauge you are reading, then the pressure switch should be shutting the pump off.  Either the switch is set too high, the tube to the switch is clogged, or the switch is not working properly.  The points in the pressure switch should open at the correct pressure and shut off power to the pump the same way a light switch does.

I like to have a pressure relief valve after the CSV for this reason.  If the pressure switch fails as it apparently has in this case, the pressure will rise to 75 PSI, (the setting if the pressure relief valve) and this valve will start dumping the 1 GPM it is getting from the CSV.  This will of course help from blowing the pipeline, but it is also importantant to give the 1 GPM coming through the CSV a place to go so as not to deadhead and burn up the pump.