5. If necessary, readjust the current limit setpoint in the
Chiller Setpoints menu.
6. Press AUTO.
The control panel also checks compressor motor wind-
ing temperature, and a start is initiated after a minimum
restart inhibit time if the winding temperature is less
than 265°F. The chilled water pump relay is energized and
evaporator water flow is proven. Next, the control panel
checks the leaving evaporator water temperature and
compares it to the chilled water setpoint. If the difference
between these values is less than the start differential
setpoint, cooling is not needed.
If the control panel determines that the difference be-
tween the evaporator leaving water temperature and
chilled water setpoint exceeds the start differential set-
point, the unit enters the initiate Start Mode and the oil
pump and Refrigerant pump and the condenser water
pump are started. If flow is not initially established
within 4 minutes 15 seconds of the condenser pump
relay energization, an automatically resetting diagnostic
“Condenser Water Flow Overdue” shall be generated
which terminates the prestart mode and de-energizes the
condenser water pump relay. This diagnostic is automat-
ically reset if flow is established at any later time.
Note:
This diagnostic does not automatically reset if
Tracer AdaptiView is in control of the condenser
pump through its condenser pump relay, since it
is commanded off at the time of the diagnostic.
It may reset and allow normal chiller operation
if the pump was controlled from some external
source.
When less than 5 seconds remain on the restart inhibit,
the pre-start starter test is conducted on Y-Delta start-
ers. If faults are detected, the unit’s compressor will not
start, and a diagnostic will be generated. If the compres-
sor motor starts and accelerates successfully, Running
appears on the display. If the purge is set to AUTO, the
purge will start running and will run as long as the chiller
is running.
Note:
If a manual reset diagnostic condition is detected
during start-up, unit operation will be locked out,
and a manual reset is required before the start-up
sequence can begin again. If the fault condition
has not cleared, the control panel will not permit
restart.
When the cooling requirement is satisfied, the control
panel originates a Shutting down signal. The inlet guide
vanes are driven closed for 50 seconds the compressor
stops, and the unit enters a
3-minute post-lube period. The evaporator pump may
continue to run for the amount of time set using Tracer
AdaptiView.
Once the post-lube cycle is done, the unit returns to auto
mode.
Daily Unit Shutdown
Note:
Refer to Start-Run Shutdown sequence in the
sequence of operation section.
1. Press STOP.
2. After compressor and water pumps shutdown, the
operator may turn Pump Contactors to OFF or open
pump disconnects.
Seasonal Unit Shutdown
D
NOTICE
Oil Sump Heater Operation!
Control power disconnect switch must remain closed
to allow oil sump heater operation. Failure to do this
will allow refrigerant to condense in the oil pump.
1. Open all disconnect switches except the control pow-
er disconnect switch.
2. Drain the condenser piping and cooling tower, if
used. Rinse with clean water.
3. Remove the drain and vent plugs from the condens-
er headers to drain the condenser. Air dry bundle of
residual water.
4. Once the unit is secured for the season, the main-
tenance procedures described under Annual Main-
tenance in the Periodic Maintenance section of this
manual should be performed by qualified Trane
service technicians.
Note:
During extended shutdown periods, be sure to
operate the purge unit for a 2-hour period every
two weeks. This will prevent the accumulation of
air and noncondensables in the machine. To start
the purge, change the purge mode to ON in the
unit control Settings Purge Menu. Remember to
turn the purge mode to Adaptive after the 2-hour
run time.
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RELEASED 10/Mar/2020 06:59:20 GMT
