Maintenance And Repair; Fault Finding Chart - Homa K 33 Serie Montage- Und Bedienungsanleitung

9. Maintenance and Repair

Before maintenance or repair disconnect the pump
from the power supply to avoid accidental starting of the
pump!
Before carrying out maintenance and service, the pump
must be thoroughly flushed with clean water. Rinse the
pump parts in clean water after dismanteling.
In case of a defect of the pump, a repair shall be car-
ried out only by the manufacturer or through an authorized
workshop. Conversions or alternations of the machine/unit
are permittes only after arrangement with the manufacturer.
Only HOMA spare parts shall be used.
In accordance with the product liability law we point out
that we shall not be liable for damages caused by our pro-
duct due to unauthorized repair by persons other than the
manufacturer or an authorized workshop or due to the use
of spare parts other than original HOMA parts. The same
product liability limitations are valid for accessories.
When unscrewing the inspection screw of the oil cham-
ber, please note that pressure may have built up in the
chamber. Do not remove the screw until the pressure has
been fully relieved.
Before maintenance or repair make sure that all rota-
ting parts stand still!
Pumps running under normal operation conditions should
be inspected at least once a year. If the pumped liquid is
very muddy or sandy or if the pump is operating conti-
nuously, the pump should be inspected every 1.000 opera-
ting hours.
When the pump is new or after replacement of the shaft
seals, check the oil level after one week of operation.
For long and trouble-free operation of the pump, following
points should be checked regularly:
- Nominal current (A): Check with amp-meter.
- Pump parts: Check for possible wear. Replace defective
parts.
- Ball bearings: Check the shaft for noisy or heavy operation
(turn the shaft by hand). Replace defective ball bearings. A
general overhaul of the pump is usally required in case of
defective ball bearings or poor motor function. This work
must be carried out by an authorized service
workshop.
- Cable entry: Make sure that the cable entry is watertight
and that the cables are not bent sharply and/or pinched.
- Oil level and oil condition in oil chamber: The oil becomes
greyish white like milk if it contains water. This may be the
result of defective shaft seal. The oil should be replaced
after 3000 operating hour. Oil type: Shell Tellus
C22, degradable HOMA-Atox available on request..
- Mechanical seals: Check the mechanical seals for wear-
out.

10. Fault Finding Chart

Before maintenance or repair disconnect the pump
from the power supply to avoid accidental starting of the
pump!
Fault
Motor does not start.
Fuses blow or motor
starter trips out imme-
diately. Caution: Do not
start again!
Pump operates, but
motor starter trips out
after a short while
Pump operates at be-
low-standard
performance and power
consumption
Pump operates, but
gives no liquid
13
Cause Remedy
• Supply failure; short- • Have the cable and
circuit; earth-leakage; motor checked and
fault in cable or motor repaired by a quali-
winding fied electrician
• Fuses blow due to use • Install fuses of the
of wrong type of fuse correct type
• Impeller blocked by • Clean the impeller
impurities
• Level switch out of • Check the level
adjustment or defecti- switch
ve
• Low setting of thermal • Set the relay in ac-
relay in motor starter cordance with the
specifications on the
pump label
• Increased current con- • Measure the voltage
sumption due to large between two motor
voltage drop phases. Tolerance:
± 10% (± 5% for ex-
plosion-proof
pumps)
• Impeller blocked by • Clean the impeller
impurities. Increased
current consumption in
all three phases
• Impeller blocked by • Clean the impeller
impurities
• Wrong direction of • Check the direction
rotation (only 3 Ph- of rotation and pos-
pumps) sibly interchange
two phases (see
section 6.4)
• Discharge valve clo- • Check the discharge
sed or blocked valve and possibly
open and/or clean
• Non-return valve blok- • Clean non-return
ked valve
• Air in pump • Vent the pump