SERVICING
38
1
2
R
C
1
2
R C
1
2
R
C
Thermostat
Modular Blower
Integrated Control Module
AC/HP Integrated
Control Module
40VA Transformer (included in
CTK0*** kit)
208/230 VAC
24 VAC
CTK04 System Wiring Using Three-Wires
between Air Handler and AC / HP
and Four Wires between Air Handler and Thermostat
CTK 04 ALTERNATE WIRING SCHEME:
Three wires should be utilized between the indoor and outdoor
units. For this wiring scheme, two wires for the data lines, 1
and 2 are required and a wire connecting the common “C”
terminals between the indoor and outdoor units. This con-
nects both commons to the same ground potential allowing
for better communication. A 40VA, 208/230 VAC to 24 VAC
transformer
must be installed
in the outdoor unit to provide
24 VAC power to the outdoor unit’s electronic control. The
transformer is included with the CTK0* kit. See kit instruc-
tions for mounting and wiring instructions. Four wires are
required between the indoor unit and thermostat.
C
OMFORT
N
ET
™ S
YSTEM
A
DVANCED
F
EATURES
The ComfortNet™ system permits access to additional
system information, advanced setup features, and advanced
diagnostic/troubleshooting features. These advanced fea-
tures are organized into a menu structure. Refer to the
Installation and Start-Up instructions shipped with your
particular CTKO*** thermostat.
Diagnostics
Accessing the air handler’s diagnostics menu provides ready
access to the last six faults detected by the air handler.
Faults are stored most recent to least recent. Any consecu-
tively repeated fault is stored a maximum of three times.
Example: A clogged return air filter causes the air handler’s
motor to repeatedly enter a limiting condition. The control will
only store this fault the first three consecutive times the fault
occurs.
NOTE:
It is highly recommended that the fault history be
cleared after performing maintenance or servicing the air
handler.
