Operating Modes - Carrier AQUASNAP 30RAP010-150 Controls, Start-Up, Operation, Service, And Troubleshooting

MODE
ITEM EXPANSION
NO.
01 CSM CONTROLLING CHILLER
02 WSM CONTROLLING CHILLER
03 MASTER/SLAVE CONTROL
RAMP LOAD LIMITED
05
TIMED OVERRIDE IN EFFECT
06
LOW COOLER SUCTION TEMPA
07
LOW COOLER SUCTION TEMPB
08
SLOW CHANGE OVERRIDE
09
10 MINIMUM OFF TIME ACTIVE
DUAL SETPOINT
13
TEMPERATURE RESET
14
DEMAND/SOUND LIMITED
15
COOLER FREEZE PROTECTION
16
LOW TEMPERATURE COOLING
17
HIGH TEMPERATURE COOLING
18
MAKING ICE
19
STORING ICE
20
HIGH SCT CIRCUIT A
21
HIGH SCT CIRCUIT B
22
MINIMUM COMP ON TIME
23
PUMP OFF DELAY TIME
24
LOW SOUND MODE
25
AO CIRCUIT A TRIO OIL MGMT
BO CIRCUIT B TRIO OIL MGMT
Table 3 — Operating Modes
Chillervisor System Manager (CSM) is controlling the chiller.
Water System Manager (WSM) is controlling the chiller.
Dual Chiller control is enabled.
Ramp load (pull-down) limiting in effect. In this mode, the rate at which leaving fluid temperature
is dropped is limited to a predetermined value to prevent compressor overloading. See Cooling
Ramp Loading (Configuration
desired, to any rate from 0.2° F to 2° F (0.1° to 1° C)/minute.
Timed override is in effect. This is a 1 to 4 hour temporary override of the programmed
schedule, forcing unit to Occupied mode. Override can be implemented with unit under
Local (Enable) or CCN (Carrier Comfort Network
Circuit A cooler Freeze Protection mode. At least one compressor must be on, and the Sat-
urated Suction Temperature is not increasing greater than 1.1° F (0.6° C) in 10 seconds. If
the saturated suction temperature is less than the Brine Freeze Point (Set Points

BR.FZ) minus 6° F (3.4° C) and less than the leaving fluid temperature minus 14° F
(7.8° C) for 2 minutes, a stage of capacity will be removed from the circuit. Or, If the satu-
rated suction temperature is less than the Brine Freeze Point minus 14° F (7.8° C), for
90 seconds, a stage of capacity will be removed from the circuit. The control will continue to
decrease capacity as long as either condition exists.
Circuit B cooler Freeze Protection mode. At least one compressor must be on, and the Sat-
urated Suction Temperature is not increasing greater than 1.1° F (0.6° C) in 10 seconds. If
the saturated suction temperature is less than the Brine Freeze Point (Set Points

BR.FZ) minus 6° F (3.4° C) and less than the leaving fluid temperature minus 14° F
(7.8° C) for 2 minutes, a stage of capacity will be removed from the circuit. If the saturated
suction temperature is less than the Brine Freeze Point minus 14° F (7.8° C) for 90 seconds,
a stage of capacity will be removed from the circuit. The control will continue to decrease
capacity as long as either condition exists.
Slow change override is in effect. The leaving fluid temperature is close to and moving
towards the control point.
Chiller is being held off by Minutes Off Time (Configuration
Dual Set Point mode is in effect. Chiller controls to Cooling Set Point 1 (Set Points

CSP.1) during occupied periods and Cooling Set Point 2 (Set Points
during unoccupied periods.
Temperature reset is in effect. In this mode, chiller is using temperature reset to adjust leav-
ing fluid set point upward and is currently controlling to the modified set point. The set point
can be modified based on return fluid, outdoor-air-temperature, space temperature, or 4 to
20 mA signal.
Demand limit is in effect. This indicates that the capacity of the chiller is being limited by
demand limit control option. Because of this limitation, the chiller may not be able to pro-
duce the desired leaving fluid temperature. Demand limit can be controlled by switch inputs
or a 4 to 20 mA signal.
Cooler fluid temperatures are approaching the Freeze point (see Alarms and Alerts section
for definition). The chiller will be shut down when either fluid temperature falls below the
Freeze point.
Chiller is in Cooling mode and the rate of change of the leaving fluid is negative and
decreasing faster than -0.5° F per minute. Error between leaving fluid and control point
exceeds fixed amount. Control will automatically unload the chiller if necessary.
Chiller is in Cooling mode and the rate of change of the leaving fluid is positive and increasing.
Error between leaving fluid and control point exceeds fixed amount. Control will automatically
load the chiller if necessary to better match the increasing load.
Chiller is in an unoccupied mode and is using Cooling Set Point 3 (Set Points

CSP.3) to make ice. The ice done input to the Energy Management Module (EMM) is open.
Chiller is in an unoccupied mode and is controlling to Cooling Set Point 2 (Set Points

CSP.2). The ice done input to the Energy Management Module (EMM) is closed.
Chiller is in a Cooling mode and the Saturated Condensing Temperature (SCT) is greater than
the calculated maximum limit. No additional stages of capacity will be added. Chiller capacity
may be reduced if SCT continues to rise to avoid high-pressure switch trips by reducing con-
densing temperature.
Chiller is in a Cooling mode and the Saturated Condensing Temperature (SCT) is greater than
the calculated maximum limit. No additional stages of capacity will be added. Chiller capacity
may be reduced if SCT continues to rise to avoid high-pressure switch trips by reducing con-
densing temperature.
Cooling load may be satisfied, however control continues to operate compressor to ensure
proper oil return. May be an indication of oversized application, low fluid flow rate or low loop
volume.
Cooling load is satisfied, however cooler pump continues to run for the number of minutes set
by the configuration variable Cooler Pump Shutdown Delay (Configuration

PM.DY).
Chiller operates at higher condensing temperature and/or reduced capacity to minimize
overall unit noise during evening/night hours (Configuration
Additional stage of capacity is added if circuit operates with only one compressor for an
accumulated time of 60 minutes.
6
DESCRIPTION
 
SLCT CRMP). The pull-down limit can be modified, if
® ) control. Override expires after each use.



FRZ

FRZ

OPT2 DELY).

COOL
 
COOL CSP.2)
 
COOL

COOL
 
OPT1

OPT2 LS.MD).