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Temporary Temperature Change
Two types of temperature changes may be made: tempo-
rary (while in the SCHEDule ON mode) or permanent
(while in SCHEDule OFF).
NOTE − If autochangeover is enabled at the time a
temperature hold is invoked, the thermostat MAY
CHANGE OVER from heating to cooling and vice versa, to
maintain the temperature hold setpoint. The
autochangeover deadband (minimum separation between
the heat and cool set points) is still used to determine
whether changeover occurs. This applies to all of the
following hold modes.
Temporary Temperature Changes (schedule
ON)
While the system is running with the schedule ON, any
change to the temperature settings may be made for the
default time (approximately 3 hours) or for as long or short
a time as you wish. Therefore, following the procedure will
set a HOLD on the schedule for a few hours or for up to 45
days. Figure 14 shows a typical screen set in the AUTO-
changeover mode. If the SYSTEM were set in HEAT,
COOL, or EM HEAT mode, only the top set of arrows ap-
pear.
1. On the home screen, press the UP or DOWN arrow to
adjust to the desired temperature.
2. A set of arrows appears to the right of the information
display; use these arrows to adjust the hold period for
as long as desired, or, if not changed, this setting will
hold for approximately 3 hours.
3. Press SAVE.
4. After saving, ON" next to the SCHED button flashes
slowly, and the information display alternates between
the following:
HOLD SETTING UNTIL
WKD MMM DD HH:MMMM
and
PRESS SCHED TO
RESUME PROGRAM
5. After the 3 hours expires, the scheduled programming
will resume, OR, press SCHED to cancel the hold.
Permanent Temperature Changes (schedule
OFF − non−programmable operation)
To make a change for an undefined time span, the sched-
ule must be turned OFF. The setpoint is maintained indefi-
nitely.
1. From the home screen, press SCHED to turn the
scheduled programming OFF.
2. Press the UP or DOWN arrow to set the temperature
to the desired temperature.
The information display field continues to display the active
mode, outdoor temperature, indoor relative humidity.
Turning the schedule back ON (press SCHED box on
home screen) will cancel a permanent hold and return to
the event-programmed mode.
HOLD SETTING UNTIL
10:49AM
OCT 10
Figure 14. Setting a Hold on the Schedule
Optional Remote Outdoor Sensor
The outdoor sensor (X2658) may be required, especially
when using Humiditrol® EDA applications. In addition to
measuring and displaying outdoor temperature, the out-
door sensor provides dew point adjustment and control for
all models. If used with this thermostat, the sensor enables
optimal heating equipment operation via programmable
balance points. The screen will display NO OUTDOOR
SENSOR until the outdoor sensor is installed, the feature
is turned on in the USER SETTINGS, in the DISPLAY
INFO option. The outdoor temperature is displayed in the
information display (lower center of the screen).
NOTE − For proper operation of Humiditrol
®
EDA applica-
tions, the outdoor sensor MUST be installed.
In many applications, the ComfortSense
®
Model L7742U
thermostat displays the temperature sensed by the remote
outdoor sensor. With the heat pump system, the remote
outdoor sensor helps determine when to turn on the
second stage of heating for optimal comfort.
When the outdoor sensor is connected, the temperature
displays in the information display area (below the indoor
temperature display).
Installing Remote Outdoor Sensor
Install the remote outdoor sensor on a northern wall of the
home, away from direct sunlight or other heat sources that
may affect its sensitivity.
IMPORTANT
The outdoor sensor must be connected to operate
a system with a Humiditrol
®
accessory.
