36
Optional Equipment
All wiring from furnace to optional equipment
MUST
conform to
local codes or, in the absence of local codes with the latest edition
of The National Electric Code, ANSI NFPA 70 and/or The
Canadian Electric Code CSA C22.1. Install wiring in accordance
with manufacturer’s instructions. The wiring
MUST
have a
minimum temperature rating of 105
°
C.
Humidifier/Electronic Air Cleaner
The furnace is wired for humidifier and/or electronic air cleaner
connection.
REDUCED FURNACE LIFE HAZARD
Failure to follow this caution may result in reduced furnace
life.
Do NOT exceed 115V/1.0 amp. maximum current load for
both the EAC terminal and the HUM terminal combined.
CAUTION
!
HUMIDIFIER -- The HUM (115) is energized when the pressure
switch closes on a call for heat. The HUM is energized when the
inducer is energized.
ELECTRONIC AIR CLEANER -- EAC is energized when there
is a blower speed call, except is NOT energized when blower
operates in the hard--wired continuous fan mode.
Furnace Control
The furnace control is preset at the factory with a fixed blower
ON
delay of 30 seconds in the heating mode. The blower
OFF
timing is preset at 140 seconds. If desired, the fan
OFF
delay can
be reset to obtain the longest delay times while still maintaining
comfort levels. See “Furnace Wiring Diagram” .
NOTE: Junction Box can be
mounted to either the left or right
side.
Models may
have 1 or 2
pressure
switches
NOTE: 115 VAC/60Hz/single--phase
Operating voltage range*: 127 VAC max, 104 VAC min.
* Permissible limits of voltage at which unit will operate satisfactorily
115V. 60 Hz
W
W
W
Low Voltage
Terminal Board
R
R
BK
Ground
Connection
Box
G
HO
T
NEUT
.
G
G
Y
G
O
N
O
FF
Representative drawing only, some models may vary in appearance.
A07726
Fig. 36 -- Electrical Connections
Furnace Control Fuse
The 24V circuit contains a 5--amp, automotive--type fuse located
on furnace control. (See Fig. 37) Any electrical shorts of 24V
wiring during installation, service, or maintenance may cause
fuse to blow. If fuse replacement is required, use only a fuse of
identical size (5 amp.)
Blower Off
Delay Jumper
FUSE
Diagnostic Light
24 VAC
HUM
115 VAC
HUM
EAC
A07727
Fig. 37 -- Control Board
DUCTWORK AND FILTER
CARBON MONOXIDE POISONING HAZARD
Failure to follow this warning could result in personal injury or
death.
Do NOT draw return air from inside a closet or utility room
where furnace is located. Return air duct MUST be sealed to
furnace casing.
!
WARNING
Installation
NOTE
: Design and install the air distribution system to comply
with Air Conditioning Contractors of America manuals and/or
NFPA pamphlets 90A and 90B or other approved methods that
conform to local codes and good trade practices.
1. When furnace supply ducts carry air outside furnace area,
seal return air duct to furnace casing and terminate duct
outside furnace space.
2. Install air conditioning cooling coil (evaporator) on outlet
side of furnace.
3. For furnaces installed without a cooling coil it is recom-
mended that the outlet duct be provided with a removable
access panel. This panel should be accessible when the
furnace is installed so the exterior of the heat exchanger
can be viewed for inspections. The access panel
MUST
be
sealed to prevent leaks.
4. If separate evaporator and blower units are used, install
good sealing dampers for air flow control. Chilled air go-
ing through the furnace could cause condensation and
shorten the furnace life.
NOTE
: Dampers (field supplied) can be either automatic or
manual. Manually operated dampers
MUST
be equipped with a
means to prevent furnace or air conditioning operation unless
damper is in the full heat or cool position.
PG9Y
AA