After Limited Shutdown - Carrier AquaEdge 23XRV Start-Up, Operation And Maintenance Instructions Manual

2. The STOP button must be pressed for one second before
the alarm light blinks once to confirm the button has been
pressed. The compressor will then follow the normal
shutdown sequence as described in the Controls section.
The chiller will not restart until the
softkey is pressed. The chiller is now in the OFF control
mode.
FAILURE TO STOP — If the alarm light does not blink after
pressing and holding the stop button for at least one second and
the chiller fails to stop, the operator should open the main
circuit breaker on the front of the control panel.
IMPORTANT: Do not attempt to stop the chiller by
opening an isolating knife switch. High intensity arcing
may occur.
Do not restart the chiller until the problem is diagnosed and
corrected.
After Limited Shutdown —
should be necessary. Follow the regular preliminary checks and
starting procedures.
Preparation for Extended Shutdown —
erant should be transferred into the pumpout storage tank (if
supplied; see Pumpout and Refrigerant Transfer Procedures) to
reduce chiller pressure and the possibility of leaks. Maintain a
holding charge of 5 to 10 psi (34 to 69 kPa) of refrigerant or
nitrogen to prevent air from leaking into the chiller.
If freezing temperatures are likely to occur in the chiller
area, drain the chilled liquid, condenser liquid, and the
pumpout condenser liquid circuits to avoid freeze-up. Keep the
waterbox drains open.
Leave the oil charge in the chiller with the oil heater and
controls energized to maintain the minimum oil reservoir
temperature.
After Extended Shutdown —
tem drains are closed. It may be advisable to flush the liquid
circuits to remove any soft rust which may have formed. This
is a good time to brush the tubes and inspect the Schrader
fittings on the optional liquid side flow devices for fouling, if
necessary.
CCN or LOCAL
No special preparations
The refrig-
Ensure the liquid sys-
Check the cooler pressure on the ICVC default screen and
compare it to the original holding charge that was left in the
chiller. If (after adjusting for ambient temperature changes) any
loss in pressure is indicated, check for refrigerant leaks. See
Check Chiller Tightness section, page 64.
Recharge the chiller by transferring refrigerant from the
pumpout storage tank (if supplied). Follow the Pumpout and
Refrigerant Transfer Procedures section, page 86. Observe
freeze-up precautions.
Carefully make all regular preliminary and running system
checks. Perform a Control Test before start-up. If the oil level
appears abnormally high, the oil may have absorbed refriger-
ant. A LOW OIL TEMPERATURE prestart alert will be
declared if the oil temperature is not greater than the CALC
EVAP SAT TEMP plus 15 F (8.3 C) or 140 F (60 C), whichever
is lower.
Cold Weather Operation —
denser liquid drops very low (55 F [13 C] minimum), the oper-
ator or tower control should automatically cycle the cooling
tower fans off to keep the temperature up. Piping may also be
arranged to bypass the cooling tower. The PIC III controls have
a Tower Fan Low control contact that can be used to assist in
this control (see the Physical Data section on page 125 for wir-
ing schematics).
Refrigeration Log —
one shown in Fig. 51, provides a convenient checklist for
routine inspection and maintenance, and provides a continuous
record of chiller performance. It is an aid in scheduling routine
maintenance and in diagnosing chiller problems.
Keep a record of the chiller pressures, temperatures, and
liquid levels on a sheet similar to that shown. Automatic
recording of PIC III data is possible through the use of CCN
devices such as the Data Collection module and a Building
Supervisor. Contact your Carrier representative for more
information.
84
When the entering con-
A refrigeration log, such as the