Fault Finding The Product; The Motor Does Not Start When The Level In The Tank Reaches The Start Level; The Motor Hums But Does Not Operate; The Motor Runs Continuously Or At Irregular Intervals - Grundfos SOLOLIFT2 CWC-3 Installation And Operating Instructions Manual

6. Fault finding the product

DANGER
Electric shock
Death or serious personal injury
‐
Before starting any work on the
product, make sure that the power
supply has been switched off and that
it cannot be accidentally switched on.
6.1 The motor does not start when the level
in the tank reaches the start level
Cause
Supply failure.
A fuse is blown. If a
new fuse blows at
once, either the cable
or motor is faulty.
The pressure switch
pipe is blocked.

6.2 The motor hums but does not operate

Cause
The impeller or
grinder is stuck.
The motor or
capacitor is defective.
The control board is
defective.
6.3 The motor runs continuously or at
irregular intervals
Cause
Water is leaking from
the inlet into the tank.
Water is leaking back
into the tank from the
outlet pipe.
The pressure switch is
defective.
Remedy
• Reestablish the power
supply.
• Replace the fuse.
• Measure the cable and
motor. If the cable or
motor is defective,
replace the defective
parts.
• Remove the pressure
switch and clean the
pipe.
Remedy
• Free the impeller or
grinder and check that
it can rotate freely.
• Replace the motor or
capacitor.
• Replace the control
board.
Remedy
• Check for leaking
appliances.
• Check the non-return
flap.
• Replace the pressure
switch unit.
6.4 The pump runs but does not deliver the
rated flow rate
Cause
The pump or tank is
blocked.
There is an air pocket
in the pump or the
vent hole in the pump
housing is blocked.
The outlet port or pipe
is blocked.

6.5 The lifting station evacuates slowly

Cause
The outlet pipe is too
long or has an
excessive number of
bends.
The pump housing is
leaky.
The hydraulics are
blocked.
Remedy
• Remove the blockage.
• Check operation of the
vent valve in the tank.
• Check that the carbon
filter is not wet.
• Check that the vent
hole in the pump
housing is not blocked.
• Remove the blockage.
• Check the non-return
flap.
Remedy
• Increase the outlet
pipe size.
• Change pipes to
reduce the number of
bends.
• Change bends to soft
bends.
• Replace the pump
housing (service part).
• Check and clean the
hydraulics and grinder.
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