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TROUBLESHOOTING
1. If a troubleshooting step needs to be performed by a qualified person, it is labeled “
To be performed by
a qualified person only.
”
2. Steps that can be performed by unqualified persons are not labeled.
3. Qualified persons are those who have been trained in avoiding the electrical hazards of working on or
near exposed energized parts. Only qualified persons may open the electrical enclosure.
4. Unqualified persons are those with little or no such training.
LOW DISCHARGE PRESSURE FAULT
Cause
Cure
Adjust the irrigation demand as required.
Flow rate greater than station capacity or
unable to pressurize the system in refill
mode (too many sprinklers on).
Verify the pressure setpoint. Has this value been changed
from the original design? If the setpoint has been increased,
the available flow will be lower. Check the pump curve to
verify the pump performance.
A large break in the irrigation piping.
Repair the piping.
Low system pressure setting is too high.
Verify n70:0 is set to 300 seconds.
System pressure transducer sensing line is
valved off or clogged.
Check the ball valve position, and/or blow out line.
System pressure transducer failure.
Replace the pressure transducer (FlowNet).
One of main pump switches in OFF position.
All pumps not running.
Consult the motor troubleshooting section if the motor won’
t
start (see Motor Won't Start).
Main pump discharge isolation valve is
closed.
Open the valve.
Pump discharge check valve leaks.
Check for foreign objects holding the valve open. Replace the
check valve if it is damaged.
The pilot valve is set too low. Adjust as necessary.
The needle valve on speed control is screwed in (closed) too
far. Adjust as necessary.
There is air inside the relief valve cover. Bleed air off the valve
top.
The ball valve(s) at the inlet and/or cover tapping(s) are
closed. Open the valves.
The optional strainer at the relief valve inlet tapping is
clogged. Disassemble and clean.
There is an obstruction under the relief valve or pilot valve
seat. Disassemble and clean.
There is a leak in the relief valve diaphragm. Replace the
diaphragm.
DSR is partially or fully open.
Bad relief valve or pilot valve seat. Rebuild or replace valve.
Low suction pressure or supply water
restriction.
Call the city if the city water pressure is lower than the normal
or published value. Check the supply piping for obstruction.