PLUS 80t with Perfect Heat™
DOWNFLOW
California Approved
331JAV
Sizes 060 thru 100
INDUCED-COMBUSTION FURNACE
The Plus 80t Downflow Furnace achieves 80 percent Annual
Fuel Utilization Efficiency (AFUE) rating. The benefits of Perfect
Heat operation in reducing sound and improving comfort put it in
a class well ahead of the competition. The Plus 80t has the kind
of overall performance needed in today’s homes. All models are
GAMA efficiency rating certified and certified for use in California
Air Quality Management Districts.
FEATURES
EFFICIENCY — The Plus 80t Induced-Combustion Gas Fur-
nace provides the efficiency customers want with 80.0% AFUE.
HOT SURFACE IGNITION — No pilot to waste gas with this
field-proven ignition system.
ALUMINIZED HEAT EXCHANGER — The patented 4-pass
heat exchanger is made of aluminized steel and backed by a
20-year Limited Warranty.
INTELLIGENT CONTROL — The Plus 80t has an intelligent
control that monitors the operation of the furnace. This control
also has a component-test feature that enables the servicing
technician to verify operation of the control; the high and low inducer; the hot surface ignitor; and high-, medium-, and lowspeed blower operation. The control features a 3-amp fuse that
protects the transformer and control. We guarantee the reliability
of the control with a 3-year Limited Warranty.
40-IN. HEIGHT — The Plus 80t cabinet height is only 40 in.
This simplifies installation in alcoves, attics, basements (ideal
for short basement), closets, and utility rooms, especially with
a taller high-efficiency cooling coil.
PREPAINTED CABINET — The Plus 80t uses prepainted sheet
metal for the cabinet. This is the same high-quality finish found
on refrigerators and other appliances today. We ensure its durability by using a galvanized steel substrate to provide superior
rust protection.
PATENTED BLOCKED VENT SAFEGUARD — Our induced-
combustion furnace has a patented blocked vent safeguard. The
safeguard switch will stop furnace operation if the vent system
becomes blocked or is not operating properly. An exclusive with
the Plus 80t furnace.
EASY INSTALLATION — The Plus 80t has many features that
make installation easier: left or right gas and electrical connections, heating and cooling blower speed selector, matching coil
sizes, accessory low-voltage connections, and many more.
QUIET OPERATION — A soft mount inducer assembly and 2-
stage slow-opening gas valve reduce sound level. The Perfect
Heat operation capability minimizes furnace and air noise for
total home comfort.
Series C
Form No. PDS 331J.60.4
*
1
28
⁄2″
20″
13
⁄16″
7
39
⁄8″
11
⁄16″
INLET
7
⁄8″ DIA
ACCESSORY
3
1
⁄4″ DIA HOLE
GAS ENTRY
OUTLET
19″
ADDITIONAL
NOTE:
LOCATED IN THE TOP PLATE
AND BOTTOM PLATE
NOTES:
1. Two additional 7⁄8-in. dia holes are located in the top plate.
2. Minimum return-air openings at furnace, based on metal duct. If flex duct is used,
see flex duct manufacturer's recommendations for equivalent diameters.
a. For 800 CFM–16-in. round or 14
b. For 1200 CFM–20-in. round or 141⁄2 x 191⁄2-in. rectangle.
c. For 1600 CFM–22-in. round or 14
d. For airflow requirements above 1800 CFM, must use entire return air opening.
7
⁄8″ DIA K.O. ARE
VENT CONNECTION
13
⁄16″
1
9
⁄8″
1
10
⁄4″
1
1
⁄16″
1
2
⁄8″
1
8
⁄4″
11
⁄16″
AIRFLOW
D
E
A
DIMPLES TO DRILL HOLES
FOR HANGER BOLTS (4 PLACES)
IN HORIZONTAL POSITION
1
⁄2 x 12-in. rectangle.
1
⁄2 x 231⁄4-in. rectangle.
11
16
⁄16″
1
13
4
⁄16″
3
⁄16″
15
2
⁄16″
5
⁄16″
1
10
⁄4″
1
⁄2″ DIA
2″
THERMOSTAT
WIRE ENTRY
7
⁄8″ DIA
ACCESSORY
7
⁄8″ DIA HOLE
POWER ENTRY
1
1
⁄2″ DIA
R.H. GAS ENTRY
7
⁄8″ DIA
ACCESSORY
1
1
⁄16″
1
2
⁄8″
1
″ TYP
5
⁄8″ TYP
DIMENSIONS (In.)
UNIT SIZE A D E VENT CONN (Dia) SHIPPING WEIGHT (Lb)
036060 14-3/16 12-9/16 12-11/16 4 145
048080 17-1/2 15-7/8 16 4 154
060100 21 19-3/8 19-1/2 4 181
A99109
ACCESSORY DOWNFLOW SUBBASE
LOCATING
TAB
B
A
Assembled
LOCATING
TAB
D
Disassembled
4
3
2
1
FACTORY-SUPPLIED
3
4
A88207
1
2
FIELD-INSTALLED
INSULATION
DIMENSIONAL DATA (In.)
PLENUM OPENING *
FURNACE WIDTH
14-3/16 11-13/16 19 13-7/16 20-3/8 4
17-1/2 15-1/8 19 16-3/4 20-3/8 3
21 18-5/8 19 20-1/4 20-3/8 2
The plenum should be constructed 1/4 in. smaller in width and depth than the plenum dimensions shown above.
FRAMED FLOOR HOLE
1 1⁄4″ TYP
WIDTH ADJUSTMENTABCD
PLENUM
OPENING
C
A88206
HOLE NO. FOR
ama
MEETS DOE RESIDENTIAL CONSERVATION
SERVICES PROGRAM STANDARDS.
Before purchasing this appliance, read important
energy cost and efficiency information available
from your retailer.
CERTIFIED
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