Wilo COF-2 Helix, Инструкция по установке и эксплуатации

Страница: 20 / 26

English
20 WILO SE 11/2019
Fault Cause Remedy
At least one of the two pumps does not
start Air intake on suction side Check the impermeability of all
connections in the suction pipework.
Check that the suction strainer is properly
submerged in water.
Foot valve strainer is permeable or
obstructed Check the impermeability of the valve and
replace it if necessary.
Significant friction losses on the suction
side Check the friction losses and make sure
that they are compatible with the NPSH of
the pumps.
Municipal water supply pressure too low
or zero Adjust the system to supply the pressure-
boosting system from a replenishment
reservoir.
Negative suction head over reservoir too
great Ensure that the minimum level of the
reservoir is compatible with the pumps’
NPSH.
Suction pipework obstructed or valve on
suction manifold closed Check that the valve is open and clean
pipework if necessary.
One pump does not start Thermal motor protection activated The pump “malfunction” warning light on
the switchgear is illuminated. Check the
thermal motor protection settings and
reset.
Magnetic circuit breaker activated Check that the motor phases have not
short-circuited.
Replace the motor if necessary.
Reset the circuit breaker.
Pump shaft blocked Disconnect the switchgear power supply,
then check that the pump shaft turns
freely. If it is blocked, proceed to
dismantle the pump.
Winding malfunction Disconnect the terminal of the motor
concerned and check the resistor at the
terminals and the stator’s insulation to
earth.
Replace the motor if necessary.
No pressure on the discharge side At least one of the pumps is deactivated See the preceding chapter, fault “At least
one of the two pumps does not start”.
Municipal water supply pressure below
minimum prescribed pressure Contact the local water supplier or replace
the pressure-boosting system. Contact
us.
One pump is obstructed by foreign
bodies Dismantle and clean the pump.
The motors are supplied by insufficient
power supply voltage Check the voltage and the connection to
motor terminals.
Random operation, pumps start
frequently Pressure sensor is defective Check settings: if sensor is unstable, it
must be replaced.
Insufficient installation capacity (or
reservoir of insufficient capacity) Install an additional storage tank or
replace with a reservoir that has greater
capacity.
Vessel pre-inflation level does not
conform Proceed to inflate the vessel.
Water storage vessel pierced Replace the vessel.
The low-water protection activates
frequently Low-water cut-out switch is set too
high Adjust and correct the cut-out switch
settings.
Municipal water supply pressure drops
when pumps activate Adjust the low-water cut-out switch to a
minimum. If the issue persists, the
municipal water supply is insufficient;
check the pressure gauge reading when
the pumps start up, or consult the
municipal water supplier.