7. Operation and maintenance
Note: The pump is not allowed to run against a
closed discharge valve for more than approx. 5 min-
utes as this will cause an increase in temperature/
formation of steam in the pump which may cause
damage to the pump.
7.1 Lubrication and maintenance
Pumps installed in accordance with these instruc-
tions require very little maintenance.
The mechanical shaft seal is self-adjusting and has
wear-resistant seal rings which are lubricated and
cooled by the pumped liquid.
The pump bearings are also lubricated by the
pumped liquid. The motor ball bearings are grease
packed and sealed for life. No further lubrication is
necessary.
Pumps from 4 kW and up have angular contact bear-
ings.
7.2 Filters
Chip trays, filters, etc. should be cleaned at regular
intervals to ensure a correct flow of liquid.
7.3 Periodic checks
At regular intervals, depending on the conditions and
time of operation, the following checks should be
made:
• Check the quantity of liquid and operating pres-
sure.
• Check that there are no leaks.
• Check that the motor is not overheating.
• Check the tripping of the motor starter.
• Check that all controls are operating satisfactorily.
If the above checks do not reveal any abnormal op-
erating details, no further checks are necessary.
Should any faults be found, check the symptoms
with section 10. Fault finding chart.
8. Service
If a pump has been used for pumping
liquids which are injurious to human health
or poisonous, it will be classified as con-
taminated.
A contaminated pump must not be sent to GRUND-
FOS for service until GRUNDFOS has received all
necessary details about the pumped liquid, etc.
Otherwise GRUNDFOS can refuse to accept the
pump for servicing.
Possible costs of returning the pump are to be paid
by the customer.
6
9. Sound pressure level
Motor
[kW]
50 Hz
0.06
<70
0.12
<70
0.18
<70
0.25
<70
0.37
<70
0.55
<70
0.75
<70
1.1
<70
1.5
<70
2.2
<70
L
[dB(A)]
pA
60 Hz
<70
<70
<70
<70
<70
<70
<70
<70
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