9
WILO SE 02/2016
English
8.5 Start
The maximum operating pressure in the installa-
tion is equal to the pressure at zero flow of the
pumps plus the water supply pressure at booster
inlet if need be.
On the control box position the mains switch on
"I" and the button of the pumps on “Auto".
The control box now ensures the automatic
operating of the booster.
ATTENTION!
Do not let the pump operate with
delivery valve closed beyond some minutes.
9. Maintenance
- No particular maintenance is recommended for
the booster when operating.
- Motor bearings are greased for life-time.
- No maintenance for the mechanical seal when
operating.
- In long period of frost and stop of the pump, it is
recommended to drain the pump by screwing off
the bottom plug.
ATTENTION!
Fill in the pump before any new
start.
10. Faults, causes and remedies
If the fault cannot be solved, please contact
WILO customer services.
Faults
Causes
Remedies
One or two pumps fail to prime
Air leak at suction
Check tightness of all suction pipe con-
nections.
Check if the tank suction strainer is
covered with water
Foot-valve strainer not tight or obstruc-
ted
Check tightness of the valve, replace it if
necessary
Large losses of head at suction
Calculate the losses of head and make
sure they are compatible with the pump
NSPH
Public water pressure too low or zero
If it recurs, it is recommended to use a tank
Suction head too high
Be sure that the minimum water level of
the tank is compatible with the NPSH of
the pumps
Suction piping obstructed or valve on
suction manifold closed
Check valve opening and clean the piping
if necessary
Pumps turn in the reverse direction
(three-phase)
Cross 2 supply wires on the motor termi-
nal blocks
One pump fails to run
Thermal relay tripped
The pump "fault" indicator on the control
box must be lit. Check the setting of the
current
Magnetic circuit breaker tripped
Switch it again. If tripping recurs, check
the output current of the motor concer-
ned. If this current is much higher than
the one mentioned on the motor type
plate, the circuit breaker is defective and
shall be replaced
Pump shaft blocked
Switch off the electric supply of the con-
trol box and then check the shaft turns
freely. If it is blocked, dismantle the
pump
Winding fault
Disconnect the terminal block of the
motor concerned. Check the network at
the terminals and the stator insulation.
Replace the motor if necessary
Contactor coil blown
Replace it
