TH144 400-144-003-C 2008-02-08 5/6

4.1 Remote Unoccupied

When the REM input is connected to a central
system or a telephone controller and a signal is
received through this input, the TH144 will
switch to the unoccupied setpoint.
• The yellow LED on top of the display turns on
when the unoccupied mode is activated
(1H1C/2H2C models only).
• The icon is displayed.
• For details on how to operate your telephone
controller (CT240/CT241), refer to its
manual.
• When this mode is activated remotely it can
only be deactivated remotely. Although, it can be bypassed for a
2-hour period (see 4.2).

4.2 2-hour Temporary Bypass

When the TH144 is in Automatic or Remote Unoccupied mode, you
can temporarily bypass the current setpoint for a 2-hour period after
which it will return to the previous mode.
Automatic (schedule programs)
• Set the desired temperature or quickly press or to use a
predefined setpoint.
Remote Unoccupied
• Set the desired temperature .
On non-programmable models, all buttons are locked except for
the buttons.
On programmable models, all buttons are locked except for the
, Day, Hour and Minute buttons.
• All other buttons or most buttons are locked depending on the
thermostat model.
• The yellow LED on top of the display remains on (1H1C/2H2C
models only), but the icon disappears.
4.3 Fan Modes (Fan button)
The TH144 thermostat is equipped with a fan button offering two fan
settings: On and Automatic.
• When On: ( ) the fan runs continuously.
• The Automatic setting allows the fan to run only during heating or
cooling cycles.

4.4 Balance Point Cut-Off

The 2H1C et 3H2C models require the AC144-02 Remote Tempera-
ture Interface and the outdoor sensor to use this function.
This option allows the user to define the temperature setpoint at
which the heat pump compressor will be cut-off and only the auxiliary
heat will be used when heating is required.
The auxiliary heat is automatically activated on a call for heat when
the outdoor temperature falls below the balance point. The heat
pump compressor will be re-activated only when the outdoor temper-
ature is at least 1°C (1°F) higher than the cut-off setpoint.
The default balance point cut-off is -8°C (17°F).
nPress and hold Heat/Cool until the setpoint is displayed.
oUse the buttons to set the new balance point.
pPress Heat/Cool to exit.

4.5 Automatic Changeover

When the AUTO mode (automatic
changeover) is selected, the thermostat
analyzes the system’s requirements and
automatically alternates between HEAT and
COOL mode to provide occupant comfort.
There are two ways to use the automatic
changeover mode:
4.5.1 Fixed Setpoint ( )
When you set the temperature using the arrow buttons, the
TH144 uses this unique temperature setpoint for temperature control.
The thermostat automatically switches to HEAT mode when the
ambient temperature drops under the temperature setpoint whereas
the COOL mode is activated when the temperature rises above the
temperature setpoint.
In order to switch modes, the ambient temperature must be
maintained over or under the control band for more than 12 minutes.
4.5.2 Predefined Setpoint ( , or )
When a predefined setpoint button is selected, the TH144 uses the
corresponding COOL and HEAT setpoint temperatures for
temperature control.
The thermostat automatically switches to COOL mode when the
ambient temperature rises above the COOL setpoint whereas the
HEAT mode is activated when the ambient temperature drops below
the HEAT setpoint.
In order to switch modes, the ambient temperature must be
maintained over or under the setpoint control band for more than 12
minutes.
q

Other Information

4.
400-144-003-C (TH144_HP) ENG.fm Page 5 Friday, February 8, 2008 10:29 AM