The pump station cycles or hunts erratically – Xylem AquaBoost CS and VS Pumping Packages User Manual
Page 44

Cause
Remedy
The diaphragm tank is faulty.
Check for a properly installed diaphragm tank. Has the
tank failed? Has the tank been charged to the proper
operating pressure before installation? (~10 psi below
the desired set point)
The pressure transducers are faulty.
Check the pressure transducers. Does the actual
mechanical gauge pressure match the pressure
displayed on the VFDs and the PLC?
The VFDs are in Local mode.
Put the VFDs in Remote mode.
A check valve is malfunctioning.
Check for malfunctioning check valves. Does the system
hold pressure when the pump package is shut down?
Replace faulty valves.
The pump station cycles or hunts erratically
Cause
Remedy
The pumps are oversized for the current demand.
Check the application. Possibly increase the size of the
bladder tank for low demand situations.
The inlet pressure is fluctuating.
—
There are leaks or broken pipes.
Check for broken pipes or leaks. Does the system
pressure decrease when the pump station is turned off?
The diaphragm tank is faulty.
Check for a properly installed diaphragm tank. Has the
tank failed? Has the tank been charged to the proper
operating pressure before installation? (~10 psi below
the desired set point)
The pressure transducers are faulty.
Check the pressure transducers. Does the actual
mechanical gauge pressure match the pressure
displayed on the VFDs and the PLC?
A check valve is malfunctioning.
Check for malfunctioning check valves. Replace faulty
valves.
There is an error in the PLC programming.
Check the customer programming on the PLC. Correct
any errors.
Troubleshooting
42
AquaBoost CS and VS Pumping Packages Installation, Operation, and Maintenance Manual