Maintenance - Xylem Lowara e-LNE Série Manuel D'installation, D'exploitation Et De Maintenance

5.4.1 Frequency of start-ups and stops
See the chapter on Technical Data for the maximum
number of hourly start-ups.
Notes for models LNTE and LNTS:
 The pump unit in use and the one in standby must
alternate regularly to ensure even distribution of the
hours of operation: make the change manually or
install an automatic controller
 When pumping domestic hot water, the pump units
should alternate at least once a day to prevent any
deposits from clogging the pump unit on standby.
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Maintenance

Precautions
Make sure you have read and understood the safety
instructions in the Introduction and Safety chapter
before starting work.
WARNING:
 Maintenance must be done by a technician
possessing the technical-professional
requirements outlined in the current
regulations
 Always wear personal protective equipment
 Always use suitable working tools
 Make sure that the drained liquid cannot
cause damage or injuries.
DANGER: Electrical hazard
 Before starting work, check that the unit is
unplugged and that the pump unit, the
control panel and the auxiliary control
circuit cannot restart, even unintentionally.
 If the pump unit is connected to the
frequency converter (optional), wait at least
10 minutes after unplugging the unit for the
residual current to dissipate.
6.1 Maintenance every 4000 hours of
operation or every year
1. Measure the pressure at zero flow rate and
compare it with the pressure measured during
initial start-up; if it has decreased by more than
15%, check the condition of the impeller, body of
the pump and wear rings.
2. Check the pump unit for unwanted noise and
vibrations.
3. Use the relief valve V to remove any air bubbles
in the pump unit.
4. Check that there is no liquid leaking from the
pump unit or pipes.
5. Check that all the screws and bolts of the pump
unit and pipes are properly fastened.
6. Check that the insulation resistance of the motor
is greater than 500 MΩ, applying a test voltage of
500 Vdc for 1 min.
7. Check the terminal board of the motor for any
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When the first of the two limits is reached
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signs of overheating and arc flashes.
8. Check the condition of the motor's cooling fan
and clean it.
9. Models LNTE and LNTS: test operation of the
flap valve by running the motors one at a time
and checking that the motor not in operation turns
in the correct direction.
6.2 Maintenance every 20000 hours of
operation or every 2 years
1. Replace the mechanical seal.
2. Replace the O-ring.
6.3 Maintenance every 20000 hours of
operation or every 5 years
Replace the motor bearings (only for greased for life
bearings).
6.4 Maintenance of the regreasable
motor bearings
Refer to the data plate and instructions of the motor
for information on the type of grease and how often it
needs to be topped up or replaced.
6.5 Blind flanges for mod. LNTE and
LNTS
If maintenance needs to be carried out on one of the
pump units, a coupling flange (optional, see Fig. 8)
can be fitted to run the other pump unit in the
meantime.
6.6 Long periods of inactivity
1. Close the on-off valve on the suction side.
2. Completely empty the pump unit.
3. Protect the pump unit against freezing.
6.7 Tightening torques of the threaded
connections
See Fig. 11.
6.8 Ordering spare parts
Identify the spare parts with the product codes directly
on the site www.lowara.com/spark.
Contact Xylem or the Authorised Distributor for
technical information.
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When the first of the two limits is reached
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When the first of the two limits is reached
en - Original instructions
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