Question
Recently our irrigation system experiences sporatic loss of prime during automatic start-up in the morning. We have a Hunter 9 Zone SRC residential controller with 9 zones, Hunter rainy day switch, a QP20 2HP Meyer irrigation pump, a Batrow pump start switch and 9 1.5" valves (5 Nelson and 4 Hunter).  All components appear to be functioning properly. 2 PVC well points at 26' and 28' respectively were sunk approx 30' apart and deliver water to the pump in 2" PVC. A standard 2" PVC checkvalve is used 1.5' from the pump. Water is delivered to the 9 valves in a 1.5" PVC manifolded system after the pump then on to the irrigation zones.

At times during auto startup, the pump appears to lose prime and will continue to run freely thru the zone run periods without prime or water. However when I shut the system off and perform a manual start, the system will slowly prime and run perfectly thru all zones. The system works during manual operations. The check valve appears to hold pressure between itself, the pump, valves and manifolding but very gradually pressure drops to 0 PSI when the system is off. During one of its tempermental periods, It takes a minute or two and sometimes a switch on and off more than once of the pump to prime during manual start of the system.        

We have a high water table (5')as we are 700' from Lake Muskegon in a high water zone. There always appears to be plenty of water. Water pressure on the pump side is approx 40 PSI Max. The pressure gage reading fluxuates wildly (between 36 & 40 PSI)during operation. The pressure valve is mounted on top of a tee on the pump. Would a reserve tank help to resolve this  tempermental loss of prime problem?

Please advise
Best Regards
Chuck Nauman
3284 Memorial Dr.
North Muskegon, MI 49445
[email protected]  

Answer
Sorry about the delay, I had to be out of town for a few days and had no access to a computer.  Your problem is somewhat baffeling to me, but I have a couple of suggestions.  Since the problem seems to be that you loose the prime between cycles, there may be a leak in your system somewhere that allows the water to move out of the supply line.  I would check the foot valve at the bottom of the well line.  Also check all of the fittings on and around your pump, tank and other appurtances for slow leaks.  If these things do not help, you may want to have a well service person inspect the system.