Carrier AquaForce 30XV140, Управление, пуск, эксплуатация, обслуживание и инструкции по устранению неисправностей

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OPERATION
Sequence of Operation
With a command to start the chiller, the evaporator pump will
start. After verifying water flow, the control will monitor the
entering and leaving water temperature. If the need for me-
chanical cooling is determined, the control decides which cir-
cuit and compressor to start. The control will start the required
compressor completely unloaded and de-energize the oil sep-
arator heater (if already energized). The control will continue
to load this circuit by increasing the VFD frequency to satisfy
cooling requirements. Once fully loaded, the control will start
the second circuit to satisfy load as required. Shutdown of each
circuit under normal conditions occurs in the opposite se-
quence to loading. Once a circuit is fully unloaded the com-
pressor is shut off and the EXV will close completely.
ACTUATED BALL VALVE (ABV)
For chillers equipped with this option (standard in most re-
gions), either one or two discharge ABVs are located in the dis-
charge line of each circuit of the unit. See Fig. 51 for a typical
ABV assembly with enclosure. The ABV is a motorized ball
valve, which is used to close the discharge line to prevent re-
frigerant migrating from condenser to the evaporator when the
circuit is off. The valve will be opened before the compressor
is started and will normally close when pressure equalizes be-
tween suction and discharge lines.
The actuated ball valves are linked to the evaporator heater op-
eration in the controls. Evaporator Heater option ( Main Menu

Configuration Menu

Factory Parameters

Evaporator
Heater Installed = yes ) must be enabled for the actuated ball
valve to operate.
See Fig. 52 for a view of a fully open ball valve with the actua-
tor removed. The flat surface at the top of the valve shaft is
parallel to the discharge line. The ball valve motor mounting
plate should be perpendicular to the discharge line at all times.
If not, adjust it by loosening the set screw on the side of the
valve, reposition assembly and tighten set screw.
See Fig. 53 for a view of the ball valve motor mounting with a
fully open valve. The motor actuator arm should be at a coun-
terclockwise position, with the valve shaft in a parallel posi-
tion. If not in a parallel position, loosen the clamping screw
and push the disengagement button to rotate the actuator arm
until it stops. Retighten the clamping screw.
ABV Manual Operation
The ABV can be operated manually as a discharge service
valve by completing the following steps:
1. Remove the actuator cover.
2. With the compressor off hold down the Disengagement
(Push) button. See Fig. 53.
3. Close the ABV by turning the shaft adapter by hand or with
a wrench so that the flats on the end of the shaft are perpen-
dicular to the discharge line.
4. Release the Push button.
5. Disconnect the control power cable to the ABV.
Dual Chiller Sequence of Operation
With a command to start the chiller, the master chiller determines
which chiller will become the lead chiller based on the configura-
tion of Lead Lag Select ( lead_sel ) and Lead/Lag Balance Delta
( ll_bal_d ). The lead chiller is always started first and the lag
chiller is held at zero percent capacity by the master chiller forcing
the lag demand limit value to 0%. If Lead Pulldown Time
( lead_pul ) has been configured, the lead chiller will continue to
operate alone for that specified time. After the Lead Pulldown
Time timer has elapsed and when the lead chiller is fully loaded,
either all available compression is on or at the master demand lim-
it value, then the lag start timer ( lstr_tim ) is initiated.
Fig. 51 — Typical ABV Assembly with Enclosure
Fig. 52 — Fully Open Ball Valve
with Actuator Removed
Fig. 53 — Ball Valve Motor
BA S E PLATE
VALVE MOTOR
VALVE MOTOR COVER
a30-4236
VALVE S HAFT
a30-4237
CLAMPING S CREW
ACTUATOR ARM
DI S ENGAGEMENT
BUTTON
MOUNTING - FULLY CLO S ED
MOUNTING - FULLY OPEN
a30-4238