Goodman Mfg VC8 - Manual (Page 18)

18
G
AS
S
UPPLY AND
P
IPING
A heat pump thermostat with three stages of heat is required to
properly use a two-stage furnace in conjunction with a heat
pump. Refer to the fossil fuel kit installation instructions for
additional thermostat requirements.
Strictly follow the wiring guidelines in the fossil fuel kit installa-
tion instructions. All furnace connections must be made to the
furnace two-stage integrated control module and the “FUR-
NACE” terminal strip on the fossil fuel control board.
115 V
OLT
L
INE
C
ONNECTION OF
A
CCESSORIES
(H
UMIDIFIER
AND
E
LECTRONIC
A
IR
C
LEANER
)
HIGH VOLTAGE !
T O AVOID PERSONAL INJURY OR DEATH DUE TO
ELECTRICAL SHOCK , DISCONNECT ELECTRICAL POWER
BEFORE SERVICING OR CHANGING ANY ELECTRICAL
WIRING .
WARNING
The furnace integrated control module is equipped with line
voltage accessory terminals for controlling power to an optional
field-supplied humidifier and/or electronic air cleaner.
The accessory load specifications are as follows:
Humidifier 1.0 Amp maximum at 120 VAC
Electronic Air Cleaner 1.0 Amp maximum at 120 VAC
Turn OFF power to the furnace before installing any accesso-
ries. Follow the humidifier or air cleaner manufacturers’ in-
structions 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 control module. The humidifier and elec-
tronic air cleaner hot terminals are identified as HUM and EAC.
The humidifier and electronic air cleaner neutral terminals are
identified as NEUTRAL. All field wiring must conform to appli-
cable codes. Connections should be made as shown.
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 humidifier terminals (HUM) are
energized with 115 volts whenever the induced draft blower is
energized. The integrated control module electronic air cleaner
terminals (EAC) are energized with 115 volts whenever the cir-
culator blower is energized.
24 V
OLT
H
UMIDIFIER
A 5" long brown wire in the wire harness at the low fire pressure
switch provides 24 VAC humidifier control. This wire is pow-
ered any time the pressure switch is closed. To connect 24
VAC HUM, connect the 24 VAC line of the humidifier to the 5”
brown wire. The connection can be made by either stripping
the wire and using a wire nut or by using a field supplied quick
connect terminal. The wiring must conform to all local and
national codes. Connect the COM side of the humidifier to the
C terminal on the furnace control board (or to the COM side of
the 24 VAC transformer). Do not connect 115V humidifier to
these terminals.
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.
Natural Gas Minimum: 5.0" w.c. Maximum:10.0" w.c.
Propane Gas Minimum: 11.0" w.c. Maximum:13.0" w.c.
Inlet Gas Supply Pressure
NOTE: Adjusting the minimum supply pressure below the limits
in the above table could lead to unreliable ignition. Gas input to
the burners must not exceed the rated input shown on the
rating plate. Overfiring of the furnace can result in premature
heat exchanger failure. Gas pressures in excess of 13 inches
water column can also cause permanent damage to the gas
valve.
At all altitudes, the manifold pressure must be within 0.3 inches
w.c. of that listed in the Specification Sheet applicable to your
model for the fuel used. At all altitudes and with either fuel, the