Instruction manual
11
defeated for one cycle by simultaneously pressing the OCCU-
PIED and UP buttons.
TEN-MINUTE STAGING TIMER — In multistage heating
or cooling, this timer prevents any higher stage from turning on
until preceding stage has been on for 10 minutes. When staging
between compressor and auxiliary heat, the time is config-
urable via Option 17. This timer is overridden if temperature
error is greater than 3 F (usually due to a large change in de-
sired temperature) and equipment stages up in 60-second
intervals.
THREE-MINUTE MINIMUM ON TIME — In normal op-
eration, when a stage turns on, it will not turn off for a mini-
mum of 3 minutes. If the set point is changed, this timer is can-
celed, allowing the equipment to turn off immediately when
the demand is removed.
Heat/Cool Set Points (Desired Tempera-
ture) —
A minimum difference of 1 F and maximum of 10 F
is enforced between heating and cooling desired temperatures.
This is done by allowing one setting to “push” the other, to
maintain this difference. This difference is adjustable via Con-
figuration Option 11.
Equipment On Indicators — When cooling equip-
ment is on, a COOL ON icon is displayed. While cooling
equipment operation is delayed by the time guard or cycle tim-
er, COOL ON will flash. The same is true for HEAT ON icon.
During second stage compressor operation a “2” will be dis-
played with the HEAT ON or COOL ON icon. When the W is
energized in a heat pump or emergency heat is available (Op-
tion 35 = On) and O/W2 is energized in an AC system, the
“auxiliary heat on” icon will be displayed.
Humidification and Dehumidification Indica-
tors — When the display module door is closed, the humidi-
fication icon will be displayed when humidification is active.
The dehumidification icon will be displayed when dehumidifi-
cation is active.
Auto Changeover — When auto changeover mode is
selected, a change from heat to cool (or vice versa) will not oc-
cur until an opposite mode demand has existed for 10 minutes.
If the set point is changed, then the 10-minute requirement is
ignored.
Emergency Heat Mode — When the control is config-
ured as a heat pump and emergency heat is selected, all Y sig-
nals are locked out, and W becomes energized upon a call for
heat. When the control is configured as an AC and emergency
heat is selected, the W signal is locked out and O/W2 becomes
energized upon a call for heat.
Dry Contact/Economizer Output — The dry con-
tact can be used for control of an auxiliary device. The dry con-
tact may be configured to be closed for a specific number of
minutes per hour for each period of the program schedule. This
can be used to operate a ventilator, damper, system fan, or other
auxiliary device. There are two terminals, D1 and D2. When
configured as a dehumidification output, the dry contact can
operate cooling equipment capable of dehumidification func-
tion. For dehumidification control, 24 volts is applied from Rc
to the dehumidifier through relay contacts D1 and D2. A sepa-
rate jumper wire is needed between Rc and one dry contact ter-
minal (such as D1).
If timed control of the system fan is required, the dry con-
tact can be used for this function. For fan control, 24 volts is
applied from Rh to G through relay contacts D1 and D2. A sep-
arate jumper wire is needed between Rh and one dry contact
terminal (such as D1).
If it is desired to operate an economizer or other ventilation
device, the D1 and D2 terminals can be connected directly to
the equipment. This will provide a dry closed contact for the
specified number of minutes per hour. See Option 19.
If timed control of the fan is required, the dry contact can be
used for this function. The G terminal can be connected to one
of the dry contact terminals with the other terminal being con-
nected to Rc and/or Rh for timed control of the fan.
TROUBLESHOOTING
If the display module does not power up after power is ap-
plied, check the Rc/Rh and C terminals for 24 VAC. If 24 VAC
is present, check the voltage between Vg and V+. This voltage
will be approximately 12 to 20 VDC. If voltage is present,
check the polarity to make sure it is wired correctly. The dis-
play will not power up if polarity is reversed.
Table 5 can be used as a troubleshooting tool for determin-
ing which outputs will be active for a particular configuration
and each operating mode.
Error Codes — If control cannot properly read space tem-
perature, display will indicate “--” and all outputs (except fan,
if on) will turn off. In the case where the installer has selected
to average the local sensor and the remote sensor, the control
display will alternate between “--” for the failed sensor and the
temperature sensed by the working sensor every 10 seconds.
The control will operate from the temperature sensed by the
working sensor.
CODE E1 — If the display module and the equipment control
module cannot communicate via two-wire connection, an E1
will be displayed.
CODE E2 — Not used.
CODE E3 — If control cannot properly read outdoor tempera-
ture, and it is needed for proper operation, the display will indi-
cate “--” in the outdoor temperature location.
CODE E4 — If control internal memory fails, E4 will be dis-
played. Replace the control.
CODE E5 — If control cannot properly read humidity, E5 will
be displayed. Replace control. If both Humidification and De-
humidification have been set to OF, the humidity value will be
shown as “–” when viewed from the humidity menu, but no E5
will be shown in the display.
WIRING DIAGRAMS
System wiring diagrams are provided for typical Carrier
equipment. See Fig. 13-27.
Table 5 – Equipment Configuration Outputs
EQUIPMENT
CONFIGURATION
COOL STAGE 1 COOL STAGE 2 HEAT STAGE 1 HEAT STAGE 2 HEAT STAGE 3 EMHEAT STAGE 1
AC Y1 Y/Y2, Y1 W/W1 W/W1, O/W2/B -- O/W2
HP (option 10 set
to C)
Y1, O/W2/B Y1, Y/Y2, O/W2/B Y1 Y1, Y/Y2 Y1, Y/Y2, W/W1 W/W1
HP (option 10 set
to H)
Y1 Y1, Y/Y2 Y1, O/W2/B Y1, Y/Y2, O/W2/B Y1, Y/Y2, O/W2/B, W/W1 W/W1