38
To ensure proper unit grounding, the ground wire should run
from the furnace ground screw located inside the furnace junc-
tion box all the way back to the electrical panel.
NOTE:
Do not
use gas piping as an electrical ground. To confirm proper unit
grounding, turn off the electrical power and perform the following
check.
1.
Measure resistance between the neutral (white) con-
nection and one of the burners.
2.
Resistance should measure 10 ohms or less.
This furnace is equipped with a blower door interlock switch which
interrupts unit voltage when the blower door is opened for servic-
ing. Do not defeat this switch.
24 V
OLT
T
HERMOSTAT
W
IRING
W
IRE
ROUTING
MUST
NOT
INTERFERE
WITH
CIRCULATOR
BLOWER
OPERATION
,
FILTER
REMOVAL
OR
ROUTINE
MAINTENANCE
.
A
REMOVABLE
PLUG
CONNECTOR
IS
PROVIDED
WITH
THE
CONTROL
TO
MAKE
THERMOSTAT
WIRE
CONNECTIONS
. T
HIS
PLUG
MAY
BE
REMOVED
,
WIRE
CONNECTIONS
MADE
TO
THE
PLUG
,
AND
REPLACED
. I
T
IS
RECOMMENDED
THAT
MULTIPLE
WIRES
INTO
A
SINGLE
TERMINAL
BE
TWISTED
TOGETHER
PRIOR
TO
INSERTING
INTO
THE
PLUG
CONNECTOR
. F
AILURE
TO
DO
SO
MAY
RESULT
IN
INTERMITTENT
OPERATION
.
STRONGLY
IMPORTANT NOTE
D
IP
SWITCH
#13 MUST
BE
SET
TO
MATCH
THERMOSTAT
TYPE
. T
O
USE
THE
CTK01
COMMUNICATING
THERMOSTAT
,
DIP
SWITCH
#13
MUST
BE
SET
TO
ON
POSITION
. T
HIS
IS
ALSO
THE
CORRECT
SETTING
FOR
A
NON
-
COMMUNICATING
2-
STAGE
THERMOSTAT
. T
O
USE
CTK02**
MODULATING
THERMOSTAT
,
CHECK
TO
MAKE
SURE
DIP
SWITCH
#13
IS
IN
THE
OFF
POSITION
(
FACTORY
POSITION
). T
HIS
IS
ALSO
THE
CORRECT
POSITION
WHEN
USING
A
NON
-
COMMUNICATING
SINGLE
-
STAGE
THERMOSTAT
.
IMPORTANT NOTE
When installed with a non-communicating thermostat, the fur-
nace integrated control module provides terminals for both “W1”
and “W2”, and “Y1” and “Y2” thermostat connections. This allows
the furnace to support the following system applications: ‘Two-
Stage Heating Only’, ‘Two-Stage Heating with Single Stage Cool-
ing’, and ‘Two-Stage Heating with Two-Stage Cooling’. Refer to
the following figures for proper connections to the integrated con-
trol module.
Low voltage connections can be made through either the right or
left side panel. Thermostat wiring entrance holes are located in
the blower compartment. The following figure shows connections
for a “heat/cool system”.
This furnace is equipped with a 40 VA transformer to facilitate use
with most cooling equipment. Consult the wiring diagram, lo-
cated on the blower compartment door, for further details of 115
Volt and 24 Volt wiring.
NOTE:
Use of ramping profiles requires a jumper between Y1
and O.
T
HERMOSTAT
“R”
REQUIRED
IF
OUTDOOR
UNIT
IS
EQUIPPED
WITH
A
C
OMFORT
A
LERT
™
MODULE
OR
IF
THE
OUTDOOR
UNIT
IS
A
PART
OF
THE
C
OMFORT
N
ET
™
FAMILY
OF
EQUIPMENT
.
IMPORTANT NOTE
AUX
DEHUM
W2
C
1
Y1
2
R
W1
Y2
G
O
24 V THERMOSTAT CONNECTIONS
Low Voltage Connections with Auxiliary Terminals
The auxiliary contacts are shipped with a factory installed
jumper. As an option, the auxiliary contacts may be wired to
a normally closed float switch. In the event of open contacts,
the furnace will be disabled until the condition is corrected.
These are 24 volt terminals fed internally, do not apply another
voltage source to these terminals.
R
Y
C
NEU
Furnace Integrated
Control Module
Remote
Condensing Unit
(Single-Stage Cooling)
Dehumidistat
[Optional]
R
Thermostat - Single-Stage Heating with Single-Stage Cooling
T
O
APPLY
A
SINGLE
-
STAGE
H
EATING
T
HERMOSTAT
,
THE
THERMOSTAT
SELECTOR
SWITCH
ON
THE
I
NTEGRATED
C
ONTROL
M
ODULE
MUST
BE
SET
ON
SINGLE
-
STAGE
.
IMPORTANT NOTE
_________________________________
____
R
Y
C
Furnace Integrated
Control Module
Remote
Condensing Unit
(Single-Stage Cooling)
Dehumidistat
[Optional]
NEU
R
Thermostat - Two-Stage Heating with Single-Stage Cooling
OPERATION
