Faults, Causes And Remedies - Wilo CO-HELIX-V 4 Instrucciones De Instalación Y Funcionamiento

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8.2 Commissioning the installation
After all preparations and checks according to
section 8.1 have been done, switch on the main
switch and set the control system to the auto-
matic mode. The pressure sensor measures the
pressure and transmits a corresponding current
signal to the control box. If the pressure is lower
than the preset starting pressure, it then switches
on the base load pump first of all (according to
the preset parameters and type of setting) and
then the peak load pumps if necessary until the
pipes are filled with water and the set pressure
has built up.
ATTENTION!
Do not let the pump operate with delivery valve
closed beyond one minute.

10. Faults, causes and remedies

DANGER! SWITCH OFF the booster before any
maintenance or repair work!
Faults
ONE OR TWO PUMPS FAIL TO PRIME
ONE PUMP FAILS TO RUN
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9. Maintenance
- No particular maintenance is recommended for
the booster during operating.
- If need be the mechanical seal can be easily
replaced.
- In long period of frost and stop it is recom-
mended to drain the pump by screwing off the
bottom plug.
ATTENTION!
Fill the pump before any new start.
Causes
Air leak at suction.
Foot-valve strainer not tight or obstruc-
ted.
Large losses of head at suction.
Public water pressure too low or zero.
Suction head too high.
Suction piping obstructed or valve on
suction manifold closed.
Thermal relay tripped.
Magnetic circuit breaker or fuses defec-
tive or blown.
Pump shaft blocked.
Winding fault.
Remedies
Check tightness of tall suction pipe
connections.
Check if the suction strainer is covered
with water.
Check tightness of the check valve,
replace it if necessary.
Calculate the losses of head and make
sure they are compatible with the pump
NSPH.
If it recurs, it is recommended to use a
tank.
Make sure that the minimum water level
of the tank is compatible with the NPSH
of the pumps.
Check valve opening and clean the piping
if necessary.
The pump „fault" indicator on the control
box must be lit.
Check the setting of the thermal relay
and reset it.
Check the direction of rotation, the cou-
pling or the current requirement of the
motor concerned.
Check that the motor phases are not in
short-circuit between them. Replace the
motor if necessary.
Reset the circuit breaker or replace the
fuses (check their ratings).
Switch off the electric supply of the con-
trol box and then check the shaft turns
freely, if it is blocked, dismantle the pump.
Disconnect the terminal board of the
terminal block and check the stator
insulation to earth. Replace the motor if
necessary.
WILO SE 01/2012