Carrier 53DFS250-FS Thermostat User Manual

HOLIDAY MODE -- This feature forces the thermo-
stat into Unoccupied for a preset duration, up to
99 days. The Holiday setup display is entered as
Press the Mode button. While holding Mode, press the Up
button for 2 seconds to enter the time period programming
The first step on the display prompts for maximum number of
Occupied periods ignore this prompt and press the Override
When active tile
display counts
down remaining
days blinking.
LI Unoccupied also
Press the Up or Down buttons to select the number of days
the thermostat will be in Holiday mode. O= Off. To exit Holiday
setup, press the Mode button.
The thermostat will enter the Holiday mode when
the clock crosses midnight.
During Holiday mode Unoccupied set points are
The Override button is active during Holiday mode.
It will override to Occupied 1 settings up to 4 hours
then return to Holiday mode. The Dry Contact
Switch is ignored.
The thermostat will exit Holiday mode at midnight of
the final programmed day. To terminate Holiday
immediately, enter the Holiday setup screen and
select 0.
SOFT START -- This feature is utilized in multiple
thermostat installations controlled by the Dry Con-
tact terminals. Assigning a unique Soft Start num-
ber to each thermostat will stagger the turn on
times, even though the Dry Contact closes for all
the thermostats connected at the same time. Each
Soft Start number represents a multiple of 30 sec-
onds from the Dry Contact closure. For example,
1 = turn on 30 seconds after Dry Contact closure,
2 = turn on 60 seconds after closure, 3 = turn on
90 seconds after closure, and so on. See page 5,
Step 14, to configure the thermostat for Soft Start.
set point range is: 35 to 99 degrees in Fahrenheit
and 7 to 35 degrees in Centigrade. When in the
modes Heat or Cool, this adjustable range is
When adjusting any Auto mode, including program-
ming Occupied and Unoccupied periods, the ther-
mostat will not allow the Heat set point to get closer
to the Cool set point than the value programmed as
the minimum difference in Step 6, page 4.
When entering the Auto mode from Cool, the Heat
and Cool set points will remain spread apart by the
amount that they were adjusted, prior to entering
For example: If the Cool set point was set to 80
while in the Cool mode and the Heat set point was
adjusted to 70 while in the Heat mode, upon enter-
ing the Auto mode the Heat and Cool set points
would be 80 and 70. Both set points would then
move up and down together, (in this example
spread by 10 degrees), by pressing the up or down
To move the Heat and Cool set points closer
together, enter the Cool or Heat mode by pressing
the Mode button, then adjust the set point(s) closer
together. Heat is limited to how close it can come to
Cool by Step 6, page 4.
REMOTE SENSORS (Optional Accessory) --
When connected to terminals RS+5, RS, and GND
on the back of the thermostat, the thermostat will
read the temperature from the Remote Sensor and
ignore the temperature sensor inside the thermo-
stat. The thermostat automatically recognizes when
a Remote Sensor is connected. When reading the
temperature from the remote, the degree icon
above the room temperature blinks once a second.
Optionam_mm,,li mm_
Remote Sensor
Optional Sensor
The Override button on
the Remote Sensor
works slightly different
than the Override button
on the front panel. Each
press of the 'External'
Override button adds
2 hours to the override
timer, if the timer was
already active, the first button press will round the
runtime to either 2:00 or 4:00.
Subsequent button presses will not wraparound as
the Override button on the thermostat does, so the
second or greater button press will set the runtime
to 4:00. The Locked feature has no effect on the
external Override button. The wired Remote Sensor
is connected to the thermostat with up to 500 ft of
20 ga. or 300 ft of 18 ga. thermostat wire. See the
Remote Sensor instructions for further details.
FACTORY DEFAULTS -- Before restoring factory
defaults, set thermostat to OFF mode. If, for any
reason it is desirable to return all stored settings
back to the factory default settings, press the Mode
button. While holding the Mode button in, press the
Down button for 2 seconds. All icons will appear.
Press and hold in the Override button until Fd
appears. This resets all factory settings. To cali-
brate room temperature, press the Mode button
once more. At this point use the Up and Down
buttons to calibrate room temperature, if needed.
Press the Mode button to return to normal
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