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60
CONTROLS OPERATION
Display Configuration
The
Configuration
→
DISP
submenu is used to configure the
local display settings.
Metric Display (METR)
This variable is used to change the display from English units to
Metric units.
Language Selection (LANG)
This variable is used to change the language of the
Comfort
Link
display. At this time, only English is available.
Password Enable (PROT)
This variable enables or disables the use of a password. The
password is used to restrict use of the control to change
configurations.
Service Password (PSWD)
This variable is the 4-digit numeric password that is required if
enabled.
Test Display LEDs (TEST)
This is used to test the operation of the
Comfort
Link display.
Modes
The
Comfort
Link controls operate under a hierarchy of command
structure as defined by four main elements: the System Mode,
the HVAC Mode, the Occupied status, and the Unit Control Type.
The System Mode is the top level that defines three main states of
the control system: Disabled, Enabled, or Test.
The HVAC Mode is the next level that defines four main states of
functional operation: Disabled, Fan Only, Cool, and Heat.
The Occupied status affects set points for cooling and
heating
in Space Sensor control mode and operation of the economizer
for indoor air quality ventilation and free cooling.
The Unit Control Type (
Configuration
→
UNIT
→
U.CTL
)
defines if temperature control is based on thermostat inputs or
space temperature sensor input.
The general operating mode of the control and the status of some
related operation lockouts are located on the display at two
locations:
Run Status
→
MODE
and
Operating Modes
→
MODE
.
System Mode (SYS)
In Run Status, the current system mode is displayed as a number
with expandable text. In Operating Modes, system mode is
displayed as expandable text.
NUMBER
RUN STATUS
EXPANDED TEXT
OPERATING MODES
EXPANDED TEXT
1
Disabled
Unit Operation Disabled
2
Enabled
Unit Operation Enabled
3
Test
Service Test Enabled
HVAC Mode (HVAC)
In Run Status, the current allowed HVAC mode is displayed as a
number with expandable text. In Operating Modes, HVAC mode
is displayed as expandable text.
NUMBER
RUN STATUS
EXPANDED TEXT
OPERATING MODES
EXPANDED TEXT
1
Disabled
HVAC Operation Disabled
2
Fan Only
Ventilation (Fan Only)
3
Cool
Cooling or Free Cooling
4
Heat
Heating
NOTE
: Optional Humidi-MiZer
™
operation is included within
Cooling mode.
Currently Occupied (OCC)
Displays the current state of assumed space occupancy based on
unit configuration and inputs.
Timed Override in Effect (T.OVR)
Displays if the state of occupancy is currently occupied due to an
override.
Linkage Active (LINK)
Displays if a linkage master in a zoning system has established
“linkage” with this unit.
Circuit OAT Lockout (C.LOC)
Displays if one or more refrigerant circuits operation is prevented
due to outdoor temperature limit lockout.
Heat OAT Lockout (H.LOC)
Displays if heating operation is prevented due to outdoor
temperature limit lockout.
Econo Cool OAT Lockout (E.LOC)
Displays if economizer operation for cooling is prevented due to
outdoor temperature limit lockout.
Unit Configuration
Many configurations that indicate what factory options and/or
field accessories are installed and other common operation
variables
are
included
in
Unit
Configuration
(
Configuration
→
UNIT
). Configuration will be done at the
factory for any factory-installed option (FIOP).
Start--Up Delay (S.DLY)
This configuration sets the control start-up delay after the power
is interrupted. This can be used to stagger the start-up of multiple
units.
Unit Control Type (U.CTL)
This configuration defines if temperature control is based on
thermostat inputs or space
temperature sensor input.
S
U.CTL = 2
(Thermostat) – The unit determines cooling
and heating demand by the state of G, Y1, Y2, W1, and
W2 inputs from a space thermostat. This value is the
factory default.
S
U.CTL = 3
(Space Sensor) – The unit determines
cooling and heating demand based on the space
temperature and the appropriate set point.
Thermostat Control Type (T.CTL)
This configuration applies only if Unit Control Type is
Thermostat (
Configuration
→
Unit
→
U.CTL = 2
). The value
determines alternative cooling and Humidi-MiZer circuit staging.
See the Cooling and Humidi-MiZer sections for more
information. The factory default value is
T.CTL
= 0
(Adaptive).
Fan On When Occupied (OC.FN)
This configuration applies only if Unit Control Type is Space
Sensor (
Configuration
→
Unit
→
U.CTL = 3
). A YES value will
operate the indoor fan whenever the unit is in the Occupied
mode. A NO value will operate the indoor fan only when heating
or cooling is necessary. The factory default value is YES.
Shut Down on IDF Failure (IDF.F)
This configuration applies only if a fan switch is installed and
configured. A YES value will enable diagnostic Alert T409 to
shut down the unit when incorrect fan status is sensed. A NO
value will still permit Alert T409 but will not cause unit
shutdown. The factory default value is YES.
Economizer Installed (EC.EN)
This configuration identifies if an economizer is installed. A YES
value enables economizer operation. A NO value disables
economizer operation. This point is repeated in the Economizer
Configuration menu (
Configuration
→
ECON
→
EC.EN
).
48/
50P
G
C
03
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