13
If it is necessary for the installer to supply additional line volt-
age wiring to the inside of the furnace, the wiring must conform
to all local codes, and have a minimum temperature rating of
105°C. All line voltage wire splices must be made inside the
furnace junction box.
The integrated control module humidifier terminal 120V
HUM-H is energized with 115 volts whenever the induced
draft blower is energized. This terminal can also be used to
provide 115 volt power to a humidifier transformer. The re
-
maining primary transformer wire would be connected to the
Line N on the control board. The integrated control module
electronic air cleaner terminals EAC-H is energized with 115
volts whenever the circulator blower is energized.
NOTE: Wire routing must not interfere with circulator blower
operation, filter removal, or routine maintenance.
PCBBF145
CONTROL BOARD
EAC-H
120 HUM-H
EAC-N
120V HUM-N
115 VAC EAC
115 VAC HUM
Connection of 24 Volt Humidifier
The integrated control module single humidifier terminal “24
VHUM” is energized with 24 volts whenever the induced draft
blower is energized. Connect the common side of the 24 volt
humidifier to the “C” terminal of the thermostat terminal strip
on the control board.
PCBBF145
Y/Y2 W R G C
24VHUM
24 VOLT HUM. &
HUMIDISTAT
To ensure proper unit grounding, the ground wire should run
from the furnace ground screw located inside the furnace
junction 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)
connection 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 servicing. Do not defeat this switch.
24 Volt Thermostat Wiring
NOTE:
Wire routing must not interfere with circulator blower
operation, filter removal, or routine maintenance.
Low voltage connections can be made through either the right
or left side panel. Thermostat wiring entrance holes are locat-
ed in the blower compartment. The following figure shows
connections for a “heat only” system and “heat/cool system”.
Furnace
Control
Furnace
Control
Remote
Condensing
Unit
Heating
Room
Thermostat
Heating/Cooling
Room Thermostat
W
W
Typical Field Wiring (24 VAC Control Circuit)
This furnace is equipped with a 40 VA transformer to facilitate
use with most cooling equipment. Consult the wiring diagram,
located on the blower compartment door, for further details of
115 Volt and 24 Volt wiring.
A single-stage thermostat with only one heating stage can be
used to control this furnace.
115 Volt Line Connection of Accessories
(Humidifier and Electronic Air Cleaner)
The furnace integrated control module is equipped with line voltage
accessory terminals for controlling power to an optional field-sup
-
plied humidifier and/or electronic air cleaner.
Turn OFF power to the furnace before installing any accessories.
Follow the humidifier or air cleaner manufacturers’ instructions for
locating, mounting, grounding, and controlling these accessories.
Accessory wiring connections are to be made through the 1/4”
quick connect terminals provided on the furnace integrated con-
trol module. The humidifier hot terminal is identified as 120V
HUM-H, its neutral terminal is identified as 120V HUM-N. The
electronic air cleaner hot terminal is identified as EAC-H, its
neutral terminal is identified as 120V EAC-N.All field wiring
must conform to applicable codes. Connections should be made
as shown. (See Connecting Line Voltage Accessories.)
Connecting Line Voltage Accessories
