Compressor Bearing Maintenance; Inspect The Heat Exchanger Tubes; And Flow Devices; Water Leaks - Carrier AquaEdge 19DV series Start-Up, Operation And Maintenance Instructions Manual

3. If the chiller is installed in a corrosive atmosphere or the
relief devices are vented into a corrosive atmosphere, in-
spect the safety relief devices at more frequent intervals.
Compressor Bearing Maintenance —
good bearing maintenance is proper lubrication. Inspect the
lubrication system regularly and thoroughly. Annual vibration
measurements are recommended to monitor overall compres-
sor status. Annual refrigerant analysis is recommended to
monitor refrigerant acid and moisture levels over time.
Excessive bearing wear can sometimes be detected through
increased vibration or increased bearing temperature. To in-
spect the bearings, a complete compressor teardown is re-
quired. Only a trained service technician should perform a
compressor disassembly. Bearings cannot be field inspected;
excessive vibration is the primary sign of wear or damage. If
either symptom appears, contact an experienced and responsi-
ble service organization for assistance. Annual compressor vi-
bration analysis and trending is recommended for compressor
preventative monitoring and maintenance.
CAUTION
If compressor requires disassembly, cleanliness is of criti-
cal importance to avoid contamination. Small amounts of
contamination can result in damage to ceramic bearings.
Inspect the Heat Exchanger Tubes and Flow
Devices
COOLER AND OPTIONAL FLOW DEVICES — Inspect
and clean the cooler tubes at the end of the first operating sea-
son. Because these tubes have internal ridges, a rotary-type
tube cleaning system is needed to fully clean the tubes. Inspect
the tubes' condition to determine the scheduled frequency for
future cleaning and to determine whether water treatment in the
chilled water/brine circuit is adequate. Inspect the entering and
leaving chilled water temperature sensors and flow devices for
signs of corrosion or scale. Replace a sensor or Schrader fitting
if corroded or remove any scale if found.
CONDENSER AND OPTIONAL FLOW DEVICES —
Since this water circuit is usually an open-type system, the
tubes may be subject to contamination and scale. Clean the
condenser tubes with a rotary tube cleaning system at least
once per year and more often if the water is contaminated.
Inspect the entering and leaving condenser water sensors and
flow devices for signs of corrosion or scale. Replace the sensor
or Schrader fitting if corroded or remove any scale if found.
Higher than normal condenser pressures, together with the
inability to reach full refrigeration load, usually indicate dirty
tubes or air in the chiller. If the refrigeration log indicates a rise
above normal condenser pressures, check the condenser refrig-
erant temperature against the leaving condenser water tempera-
ture. If this reading is more than what the design difference is
supposed to be, the condenser tubes may be dirty, water flow
may be incorrect, or non-condensables have contaminated the
refrigerant circuit. To resolve check the purge status. If purge is
operating normally and does not have excessive run time that
may be an indication to double check pressure transducer and
temperature readings along with flow.
During the tube cleaning process, use brushes specially de-
signed to avoid scraping and scratching the tube wall. Contact
your Carrier representative to obtain these brushes. Do not use
wire brushes. Hard scale may require chemical treatment for its
prevention or removal. Consult a water treatment specialist for
proper treatment.
The refrigerant moisture indicator on
Water Leaks —
the refrigerant motor cooling line along with the moisture
indicator located in the liquid refrigerant feeding the com-
pressor bearings (Fig. 2) indicates whether there is water or
air leakage during chiller operation. Water leaks should be
repaired immediately.
The key to
The chiller must be dehydrated after repair of water leaks
or damage may result. See Chiller Dehydration section,
page 20.
Water Treatment —
water may result in corrosion, scaling, erosion, or algae. The
services of a qualified water treatment specialist should be ob-
tained to develop and monitor a treatment program.
Water must be within design flow limits, clean, and treated
to ensure proper chiller performance and reduce the poten-
tial of tube damage due to corrosion, scaling, erosion, and
algae. Carrier assumes no responsibility for chiller damage
resulting from untreated or improperly treated water.
Inspect the VFD —
off the chiller, open and tag all disconnects supplying power to
the starter.
The motor leads must be disconnected from the VFD
before an insulation test is performed. The voltage gener-
ated from the tester can damage the drive components.
Failure to follow these procedures may result in personal
injury or damage to equipment.
TO AVOID an electric shock hazard, verify that the voltage
on the bus capacitors has discharged completely before ser-
vicing. Check the DC bus voltage at the power terminal
block by measuring between the +DC and –DC terminals,
between the +DC terminal and the chassis, and between the
–DC terminal and the chassis. The voltage must be zero for
all three measurements.
DC bus capacitors retain hazardous voltages after input
power has been disconnected. An isolated multimeter will
be needed to measure DC bus voltage and to make resis-
tance checks.
After disconnecting input power, wait 5 minutes for the DC
bus capacitors to discharge and then check the voltage with
a voltmeter rated for the DC bus voltage to ensure the DC
bus capacitors are discharged before touching any internal
components. Failure to observe this precaution could result
in severe bodily injury or loss of life.
The disconnect on the starter front panel does not always
de-energize all internal circuits. Open all internal and
remote disconnects before servicing the starter. Failure to
follow this procedure may result in personal injury by elec-
tric shock.
45
CAUTION
Untreated or improperly treated
CAUTION
Before working on any starter, shut
CAUTION
CAUTION
WARNING
WARNING