SERVICE
G20RE
UNIT
INFORMATION
Page 1
1994 Lennox Industries Inc.
Corp. 9419 – L9
Litho U.S.A.
G20RE SERIES UNITS
I – INTRODUCTION
G20RE and G20RXE series units are mid–efficiency
downflow gas furnaces with Duracurve
heat ex-
changers formed of aluminized steel. G20RE units
come in heating capacities of 50,000 to 150,000 Btuh. In
cooling applications, blowers are equipped to handle
up to 5 tons of cooling capacity. Refer to Engineering
Handbook for proper sizing.
Units are factory supplied for use with natural gas. A
conversion kit to LPG operation is available for the
G20RE only. All units are equipped with an electronic
ignition. G20RXE models meet the California Nitrogen
Oxides (NO
x
) Standards and California Seasonal Effi-
ciency requirements. All units use a redundant gas
valve to assure safety shut–off as required by A.G.A.
Featured on G20RE series is a burner box damper as-
sembly located on the intake side of the burners. A
damper door in the burner box shuts during unit off
cycles to retain heat in the unit. A damper prove switch
ensures that damper is open before gas valve is ener-
gized. Since the G20RE furnaces have atmospheric
burners there is no induced draft motor. All G20RE
units have a draft diverter which allows the use of stan-
dard single wall vent connectors.
SPECIFICATIONS
(continued on next page)
Model No.
Input Btuh
Output Btuh
*A.F.U.E.
Flue connection (in. diameter)
Temperature rise range
High static certified by A.G.A.(in wg.)
Gas piping size
I.P.S. (in.)
Blower wheel nominal diameter x width (in.)
Blower motor hp.
Electrical characteristics
Natural
**
LPG
G20RQ2/3E-50
G20RQ3E–75
G20RQ4E-75
G20RQ3/4E-100
50,000
40,000
78.0%
4 Round
20-50
.50
1/2
1/2
10 x 8
1/3
2, 2–1/2 or 3
Tons of cooling (add–on)
58,000
78.0%
78.0%
78.0%
75,000
59,000
75,000
79,000
4 Round
4 Round
5 Oval
50-80
30-60
50-80
.50
.50
.50
1/2
1/2
1/2
1/2
1/2
1/2
10 x 8
11 x 9
11 x 9
1/3
1/2
1/2
*Annual Fuel Utilization Efficiency based on D.O.E. test procedures and according to F.T.C. labeling requirements.
Isolated combustion system rating for non–weatherized furnaces.
•
G20RQ2/3XE-50
•
G20RQ3XE–75
•
G20RQ4XE-75
•
G20RQ3/4XE-100
100,000
California Seasonal Efficiency– “X” Models
72.1%
74.8%
72.0%
74.5%
Number and Size of Filters (in.)
(2) 20 x 10 x 1
(2) 20 x 10 x 1
(2) 20 x 12 x 1
(2) 20 x 12 x 1
2, 2–1/2 or 3
3, 3–1/2 or 4
3, 3–1/2 or 4
•
Not Available with LPG.
**LPG kit must be ordered extra for field changeover.
120 volts — 60 hertz — 1 phase (less than 12 amps) — All Models
