49
1
2
R C
1
2
R
C
CTK0*
Thermostat
ComfortNet Compatible
Furnace Integrated
Control Module
ComfortNet Compatible
AC/HP Integrated
Control Module
40VA Transformer
(included in CTK01 kit)
208/230 VAC
24 VAC
1
2
R C
System Wiring using Two-Wires between Furnace and AC/HP
and Four-Wires between Furnace and Thermostat
1
2
R C
C
Y
ComfortNet Compatible
Furnace Integrated
Control Module
CTK0*
Thermostat
Non-
Compatible
Single Stage AC
ComfortNet
G
W1 W2
Y1
Y2
O
1
2
R
C
4-Position Connectors
from CTK0*
Thermostat Kit
System Wiring between Furnace and Non-
Communicating Compatible Single Stage Air Conditioner
CTK0* W
IRING
NOTE:
Refer to
Electrical Connections
for 115 volt line connections
to the furnace.
NOTE:
A removable plug connector is provided with the control
to make thermostat wire connections. This plug may be removed,
wire connections made to the plug, and replaced. It is
strongly
recommended that multiple wires into a single terminal be twisted
together prior to inserting into the plug connector. Failure to do so
may result in intermittent operation.
Typical 18 AWG thermostat wire may be used to wire the system
components. One hundred (100) feet is the maximum length of
wire between indoor unit and outdoor unit, or between indoor unit
and thermostat. Wire runs over (100) feet require larger gauge
wire.
F
OUR
-W
IRE
I
NDOOR
AND
O
UTDOOR
W
IRING
Typical ComfortNet™ wiring will consist of four wires between the
indoor unit and outdoor unit and between the indoor unit and
thermostat. The required wires are: (a) data lines, 1 and 2; (b)
thermostat “R” (24 VAC hot) and “C” (24 VAC common).
T
WO
-W
IRE
O
UTDOOR
, F
OUR
-W
IRE
I
NDOOR
W
IRING
As few as two wires can be utilized between the indoor and out-
door units. For this wiring scheme, only the data lines, 1 and 2,
are needed between the indoor and outdoor units. A 40VA, 208/
230 VAC to 24VAC transformer must be installed in the outdoor
unit to provide 24VAC power to the outdoor unit’s electronic con-
trol. The transformer is included in selected communicating
thermostat kits. See kit instructions for mounting and wiring instructions. Four wires are required between the indoor unit and
thermostat. If using a communicating thermostat kit that does not include a transformer in a dual fuel system, the accessory
transformer kit TFK01 should be used.
NOTE:
Use of the accessory transformer is recommended if installing a dual fuel/fossil fuel system. Failure to use the transformer
in the outdoor unit could result in over loading of the furnace transformer.
C
OMFORT
N
ET
™ C
OMPATIBLE
F
URNACE
WITH
N
ON
-C
OMFORT
N
ET
COMPATIBLE
S
INGLE
-S
TAGE
A
IR
C
ONDITIONER
Four wires are required between the furnace and thermostat. Two wires are required between the furnace control and single stage air
conditioner. For this system configuration, the “Y1” terminal on the integrated furnace control becomes an output rather than an
input. The “Y1” connection to the outdoor unit is made using both of the 4-position thermostat connectors in the CTK0* kit.
Remove the red keying tabs from the on-board connector block and position both 4-position connector such that “1”, “2”, “R”, “C”,
and “Y1” positions are filled.
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 features are organized into a menu structure. The menus are accessed and navigated as
described in the instructions provided with the communicating control.