20
Accessories Wiring
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 single humidifier terminal (HUM)
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 remaining primary trans-
former wire would be connected to the Line N on the control
board.The integrated control module electronic air cleaner
terminal (EAC) is energized with 115 volts whenever the circu-
lator blower is energized.
In addition, the control is equipped with a dedicated humidifica-
tion relay which is available through ¼ inch terminals HUM-IN
and HUM-OUT. Similar to the HUM terminal, when utilizing
legacy connections, this relay will be closed during normal
heating operation. HUM IN must be powered with the desired
voltage (24 vac from the R terminal or 115 vac from L1 terminal).
The internal relay will close during a call for heat. Also, the
control can provide additional humidification features when wired
to a communicating thermostat (1, 2, R, C connections). If the
communicating thermostat is not capable of providing a hu-
midification call, this dedicated relay will function exactly as
mentioned above with a legacy setup. If the communicating
thermostat is capable of providing a humidification call the user
is now provided with 3 modes of operations which can be se-
lected within the thermostat user menu.
1. ON: Humidifier is turned on with a heat demand.
2. OFF: Humidifier remains off (relay never closes).
3. IND: Humidifier will cycle with humidification demand,
independent of heat demand. This mode allows the user
to select one of 4 fan speeds (25, 50, 75, and 100%).
NEUTRAL
HU
M
-OU
T
HUM-
IN
24 V
OLT
H
UMIDIFIER
A 24 volt humidifier can be powered by feeding one of the HUM
terminals with a field installed wire from the R terminal or by
connecting to the NO side of the low fire pressure switch.
A
UXILIARY
A
LARM
S
WITCH
The control is equipped with a 24VAC Auxiliary Alarm Input (12
inch purple wire attached to pin 6 of 15 pin connector) which
can be utilized with communicating mode setups (typically used
for condensate switch wiring but could be used with compat-
ible C0
2
sensors or Fire Alarms).
Legacy mode use
In a legacy system (Non-communicating), this auxiliary alarm
input is not operational. Any auxiliary alarm switch must be
used to interrupt Y1 signal either to IFC or to UC.
Communication mode use
This feature can be activated or deactivated through the ther-
mostat user menus. By default, an AUX switch is normally
closed and opens when the water level in the evaporator coil
base pan reaches a particular level. The control will respond by
turning off the outdoor compressor and display the proper fault
codes. If the AUX switch is detected closed for 30 seconds,
normal operation resumes and error messages are no longer
displayed. Installer must wire control voltage (24VAC) to AUX
switch to ensure the Auxiliary Alarm Input has 24VAC during
normal operation.
G
AS
S
UPPLY
AND
P
IPING
The furnace rating plate includes the approved furnace gas in-
put rating and gas types. The furnace must be equipped to
operate on the type of gas applied. This includes any conver-
sion kits required for alternate fuels and/or high altitude.
CAUTION
T
O
PREVENT
UNRELIABLE
OPERATION
OR
EQUIPMENT
DAMAGE
,
THE
INLET
GAS
SUPPLY
PRESSURE
MUST
BE
AS
SPECIFIED
ON
THE
UNIT
RATING
PLATE
WITH
ALL
OTHER
HOUSEHOLD
GAS
FIRED
APPLIANCES
OPERATING
.
Inlet gas supply pressures must be maintained within the ranges
specified in the following table. The supply pressure must be
constant and available with all other household gas fired appli-
ances operating. The minimum gas supply pressure must be
maintained to prevent unreliable ignition. The maximum must
not be exceeded to prevent unit overfiring.