Advanced setup, About advanced features and operation – Carrier 53DFS250-SL User Manual
Page 5
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Advanced Setup
Select thermostat
operation in degrees
Fahrenheit or Celsius.
C
f
Select the display back
light always On, or Off
after 8 seconds.
ON
Adjust the preoccupancy
fan purge timer.
0 - 3 hours.
0:00 = off
fl-nn
u-yy
Select the unit ID for
‘Soft Start'. This is used
in multiple installs to
stagger equipment turn
on times. 0 = off.
Each Number-(SOseconds)
second delay.
(0to99)
n
U
Press the Mode button. While holding the Mode, press the Program button
leave the Setup screens. If no buttons are pressed, the display will leave the
setup screens after 30 seconds.
Advanced Setup Table
STEP
NO.
DESCRIPTION
RANGE
FACTORY
DEFAULT
1
Time of day clock set
24 hour
12:00 Am
2
Day of the week
Su - Sa
Mo
3
Heat Pump
Off/On
Off
4
Deadband or Temperature swing
1 -6 F
2 F
5
Forced minimum difference heat/
cool
0 -6 F
2 F
6
Cycles per hour
d, d1,2-6
6
7
Security Levels
0 - 3
0
8
Maximum ailowabie Heat set point
35 - 99 F
80 F
9
Minimum aiiowable Cool set point
35 - 99 F
65 F
10
Fahrenheit or Celsius
F/C
F
11
Thermoglow^'^^ backlight
Off/On
On
12
Fan Purge timer
0:00-3:00
min.
0:00 min.
13
Soft Start
0 - 99
0
About Advanced Features and Operation
CLOCK BACKUP — In the event of a power loss,
the thermostat internal clock will continue to keep
proper time for a minimum of 48 hours without
external power or batteries.
TWO-STAGE OPERATION — The Second Stage of
heat (Heat pump models only) is turned on when
(1) the first Stage has been on for a minimum of two
minutes, and (2) the temperature spread from the
set point is equal to or greater than: the setpoint
temperature plus the deadband, plus 2 degrees.
2 degrees 2 degrees
Dead
Band
Dead
Band
2 degrees 2 degrees
/ / f \
\
''andStage tsfStage Heat Cool istStage
turnon turnon Set Point Set Point tumcn
3rd Stage 2nd Stage 1 st Stage
High
yed
Low
MINIMUM HEAT/COOL SET POINT DIFFERENCE
— The Heat and Cool set point temperature will not
be allowed to come any closer to each other than
the value set in Advanced Setup Step 5, on page 4.
This minimum difference is enforced during Auto
changeover and Program On operation.
ENERGY SAVING SMART FAN — It Fan On is
selected, the fan will run continuously at all times,
except in Off, and will only run if there is a heating
or cooling demand in Unoccupied periods.
OVERRIDE — As explained on page 3, pressing
the Override button during a programmed, Unoccu
pied period will force the thermostat into Occupied
1, temporarily, up to 4 hours. If the Override button
is pressed during an Occupied period, the thermo
stat will be forced into Unoccupied and the occu
pied number (1,2 or 3), it was forced out of will be
turned off, only tor that day.
During Override periods the set point temperature
may be adjusted, but they will not be remembered
after Override ends.
HEAT — First Stage = Heat Pump. Second Stage =
Heat Pump and Electric Heat.
FAN PURGE TIMER — When this feature is acti
vated, the fan will turn on during Unoccupied at a
preset amount of time prior to Occupied 1. This pre
occupancy fan purge timer may be set as instructed
on this page, Step 12, from 0 to 3 hours. 0 - this
feature turned off.
KEYPAD LOCK — To prevent unauthorized use of
the thermostat, the front panel buttons may be dis
abled. To disable, or ‘lock’ the keypad, press and
hold in the Mode button. While holding the Mode
button in, press the Up and Down buttons in
together. The Locked icon will appear on the
display.
Press all 3 for
Keypad Lockout'
o
ON
Locked
8S
55
To unlock the buttons, again press and hold the
Mode button. While holding the Mode button in,
press the Up and Down buttons in together. The
Locked icon will disappear from the display.
DRY CONTACT SWITCH — The terminals are ‘nor
mally open’. Closing or completing the circuit will
cause the thermostat to enter Occupied 1. This fea
ture allows an external device such as a Central
Time Clock, Occupancy Sensor, or a Telephone
activated device to force 1 or more thermostats into
Occupied 1. For the Dry Contact to work the ther
mostat must be in Program On. Set Occupied 1
to Off for all 7 days, so the Contact closure will be in
control. When the thermostat is forced into
Occupied 1 via the Dry Contact closure, the icon
Occupied 1 will blink.
CK1
tJGND
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