Honeywell AC-140-7 Thermostat User Manual


 
1. PROGRAMMING T775A/B/M SERIES 2000 CONTROLLER
13 62-0254–03
1. PROGRAMMING
The controller must be programmed before being placed
into service.
IMPORTANT
During programming, the controller is live at all
times. For example, the contacts may open and
close when adjusting the setpoint.
The Programming process uses a hierarchical menu
structure that is easy to use. You press the W and X
arrow buttons to move forward and backward through the
menus.
NOTES:
1. The controller interface is intuitive. You may
find that you do not need the following proce-
dure instructions to program the controller.
You may want to use this procedure simply as
a reference to locate the particular option or
parameter of interest.
2. The menus can display only those relays that
are defined in Setup (see “2.3.2. NBR OF
RELAYS” on page 24). For example, if you
configure only two relays, then only two
relays display on the appropriate menus.
3. If you press the HOME button or there is no
keypad activity for four minutes, you exit Pro-
gram mode and return to the home screen.
4. If you press the MENU button, you exit Pro-
gram mode and return to the menu.
Setpoint and Differential
The following describes the relationship between setpoint
and differential for heating and cooling. These settings are
programmed for each output relay.
Heating Mode Setpoint and Differential
In heating mode, the differential is below the setpoint. The
relay de-energizes when the temperature rises to the
setpoint. As the temperature drops to the setpoint minus
the differential, the relay energizes.
Cooling Mode Setpoint and Differential
In cooling mode, the differential is above the setpoint. The
relay de-energizes when the temperature falls to the
setpoint. As the temperature rises to the setpoint plus the
differential, the relay energizes.
Setpoint High Limit
You can set a single irreversible setpoint high limit
maximum value, which is applied to all outputs.
Adjust the setpoint (at any output) to the desired
maximum setpoint. Then, simultaneously press the
home, W, and X buttons and continue to press all three
buttons for five seconds to set the setpoint high limit
maximum to this value.
NOTE: You must press all three buttons at exactly the
same time for this action to occur.
IMPORTANT
1. This action sets the maximum setpoint value of
all outputs to the setpoint high limit maximum.
2. Setting the high limit setpoint maximum is irre-
versible. If you perform the action inadvertently
and this setpoint adversely affects the control of
your system, you must replace the controller.