Specifications

Table 12 — Operational and Mode Display Codes
CODE DESCRIPTION
LOCAL OFF Unit is off. LOCAL/OFF/REMOTE switch is
in OFF position or LOCAL/OFF/REMOTE
switch is in REMOTE position and remote
contacts are open.
CCN OFF Unit is off. LOCAL/OFF/REMOTE switch is
in LOCAL position and CCN control is
enabled (Stop state) or CCN is enabled
(Stop state) with LOR switch in REMOTE
position and remote contacts closed.
CLOCK OFF Unit is off due to internal clock schedule.
LOR switch is in LOCAL position.
LOCAL ON Unit is on. LOR switch is in LOCAL position
and CCN is disabled or LOR switch is in
REMOTE position with contacts closed and
CCN is disabled.
CCN ON Unit is on due to CCN command. LOR
switch is in LOCAL position and CCN is
enabled (Run state) or LOR switch is in
REMOTE position with contacts closed and
CCN is enabled (Run state)
CLOCK ON Unit is on due to internal clock schedule or
occupied override function. LOR switch is
in LOCAL position.
DUAL SP ACTIVE
(1st SP)
Dual set point is in effect. In this mode, unit
continues to run in an occupied condition,
and leaving fluid set point is automatically
controlled to the CSP1 set point in the SET
POINT function.
DUAL SP ACTIVE
(2nd SP)
Dual set point is in effect. In this mode, unit
continues to run in unoccupied condition,
but leaving fluid set point is automatically
increased to a higher level (CSP2 set point
is in SET POINT function).
TEMPERATURE
RESET ACTIVE
Temperature reset is in effect. In this mode,
unit is using temperature reset to adjust
leaving fluid set point upward, and unit 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
ACTIVE
Demand limit is in effect. This indicates that
capacity of unit is being limited by demand
limit control option. Because of this
limitation, the unit may not be able to
produce the desired leaving fluid
temperature. Demand limit can be controlled
by a switch or 4 to 20 mA signal.*
FSM
CONTROLLING
Flotronic™ System Manager (FSM) is
controlling the chiller.
RAMP LOADING
ACTIVE
Ramp load (pulldown) limiting is 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 CRAMP set point in the
SET function in (page 25). The pulldown limit
can be modified, if desired, to any rate from
0.2° F to 2° F (0.1° to 1° C)/minute.
TIMED OVERRIDE
ACTIVE
Timed override is in effect. This isa1to
4 hour temporary override of the pro-
grammed schedule, forcing unit to occupied
mode. Override can be implemented with
unit under LOCAL/REMOTE or CCN control.
Override expires after each use.
WSM
CONTROLLING
Water System Manager is controlling the
chiller.
SLOW CHANGE
OVERRIDE
Slow change override is in effect. The
leaving fluid temperature is close to and
moving towards the control point.
CODE DESCRIPTION
OFF TO ON
DELAY ACTIVE
Chiller is being held off by Minutes Off Time
found by keying . Also, normal
operation of the chiller includes a minimum
1.5 minute delay after a capacity stage
change has been made. This delay is
adjustable from 1.5 to 6 minutes.
LOAD LIMIT
ACTIVE
This function determines the maximum
allowable capacity that can be running and
is accomplished through the Flotronic
System Manager. The unit may not be able
to produce the desired leaving fluid
temperature.
2 CHILLR LEAD
LAG ACTIVE
Future Use.
2 CHILLR LL
COMM FAILURE
Future Use.
CIRCUIT A LOW
DISCHARGE
SUPERHT
If the circuit discharge superheat is less
than 15° F (8.3° C), the capacity control
routine will not add any stages (to either
circuit).
If the compressor has been running for at
least 3 minutes, the EXV will not be
opened any further. If the circuit
discharge superheat is less than 10° F
(5.6° C) and falling, the circuit EXV will
be closed 50 steps every 10 seconds.
If the discharge superheat is less than
5° F (2.8° C) and falling, a circuit loader
will be deenergized every 30 seconds.
The final stage will not be unloaded
unless an alarm condition is present.
CIRCUIT B LOW
DISCHARGE
SUPERHT
See description for Circuit A above.
CIRCUIT A
HIGH SCT
If the circuit is running and the Saturated
Condensing Temperature (SCT) is greater
than the Maximum Condensing
Temperature Set point (MCT_SP) minus
12° F (6.7° C), the control will not add
any stages.
If the SCT is greater than the MCT_SP
plus 5° F (2.8° C), the circuit will be
unloaded and shut down if necessary. If
the SCT is greater than the MCT_SP plus
2° F (1.1° C) for one minute, a loader will
be deenergized.
If the SCT is greater than the MCT_SP
minus 4° F (2.2° C), the control will
compare the maximum operating
pressure set point (MOP_SP) with the
modified MOP_SP (MOP_CTRL).
If the MOP_CTRL is greater than the
MOP_SP, the mode will be cleared.
Otherwise the control will display the
high SCT override mode. The capacity
control routine will not add any stages. If
the circuit is at its lowest capacity, this
mode will be ignored.
CIRCUIT B
HIGH SCT
See description for Circuit A above.
LEGEND
CCN — Carrier Comfort Network
CSP — Cooling Set Point
CRAMP — Cooling Ramp Loading
EXV — Electronic Expansion Valve
LOR — Local/Off/Remote
SP — Set Point
WSM — Water System Manager
*A field-supplied 500 Ohm
1
⁄ 2 W resistor must be installed across the
input terminals when usinga4to20mAsignal.
Table 13 — Reading Current Operating Modes
KEYPAD ENTRY DISPLAY
MODES :MODE_TBL
CCN ON
DEMAND LIMIT
ACTIVE
24