Lennox G24M SERIES Unit Information

Service Literature

G24M series units are mid-efficiency gas furnaces manufac-
tured with tubular steel heat exchangers formed of alumi-
nized steel. G24M units are available in heating capacities of
45,000 to 140,000 Btuh and cooling applications up to 5
tons. Refer to Engineering Handbook for proper sizing.
Units are factory equipped for use with natural gas. A kit is
available for conversion to LPG operation. Early model G24M
units use electronic (direct spark) ignition. Late model G24M
model units feature the Lennox SureLightT silicon-nitride
ignition system. The G24MX unit meets the California Nitro-
gen Oxides (NO ) Standards and California Seasonal Effi-
x
ciency requirements. All units use a redundant gas valve to
assure safety shut-off as required by A.G.A. or C.G.A.
Units may be installed in upflow, downflow or horizontal posi-
tion. The heat exchanger is designed for upright or horizon-
tal use only. When the unit is installed in the downflow posi-
tion, the heat exchanger is field removed and reinstalled so it
is upright when the cabinet is inverted. No field conversion is
required when the unit is installed in the horizontal position.
The heat exchanger, burners and manifold assembly can
easily be removed for inspection and service by simply dis-
connecting gas, unplugging wiring harness and spark wires
and removing four screws holding the heat exchanger in
place. Then the heat exchanger slides out of the cabinet.
Model No.
Input Btuh (kW)
Output Btuh (kW)
lA.F.U.E.
California Seasonal Efficiency
Flue size connection diameter — in. (mm) round
Temperature Rise range — _F (_C)
High static certified by A.G.A./C.G.A. — in wg. (Pa)
Gas Piping Size I.P.S. Natural or LPG/propane
Blower wheel nominal Blower wheel nominal
diameter x width
Blower motor output — hp (W)
Nominal cooling Nominal cooling
that can be added
Shipping weight — lbs. (kg) 1 package
Electrical characteristics
LPG/propane kit
Twinning Kit
Up-Flow/Horizontal Filter and Filter Rack Kits
}No. & size of filters - in. (mm)
Catalog No.
¡Down-flow ¡Down-flow
No. & Size of Filters — in. (mm)
Filter Kit
Down-flow Combustible Floor Base
Sidewall Power Venting Kit
Hanging Bracket Kit
lAnnual Fuel Utilization Efficiency based on U.S. DOE test procedures and according to FTC labeling regulations. Isolated combustion system rating for non-weatherized
furnaces.
}Polyurethane frame type filter is furnished with kit.
¡Filters are not furnished with kit and must be ordered extra.
Corp. 9723-L12
Revised 07-2001
G24M SERIES UNITS
Specifications
G24M2(X)-45
45,000 (13.2)
36,900 (10.8)
80.1%
75.4%
30 - 60 (17 - 33)
in.
mm 229 x 178
1/4 (187)
Tons 1, 1-1/2 or 2
kW 3.5, 5.3 or 7.0
130 (59)
b Optional Accessories (Must Be Ordered Extra) b
All specifications in this manual are subject to change. Pro-
cedures outlined in this manual are presented as a recom-
mendation only and do not supersede or replace local or
state codes. In the absence of local or state codes, the
guidelines and procedures outlined in this manual (except
where noted) are recommended only and do not constitute
code.
G24M2-60 G24M3(X)-60
60,000 (17.6)
49,200 (14.4)
80.5% 80.5%
76.4% 75.9%
3 (76)
.50 (125)
1/2 (13)
9 x 7 10 x 7
254 x 178
1/3 (224)
2, 2-1/2 or 3
7.0, 8.8 or 10.6
120 volts — 60 hertz — 1 phase (less than 12 amps) All models
LB-69845L (38K84)
96J69 — 5 lbs. (2 kg)
Single (32J02) Ten Pack (66K64)
(1) 16 x 20 x 1 (406 x 508 x 25)
LB-69843A (32J01) — 3 lbs. (1 kg)
(2) 16 x 20 x 1 (406 x 508 x 25)
LB-79239A (67J91) — 10 lbs. (4 kg)
79J15 — 25 lbs. (11 kg)
LB-69957 (46J66) — 15 lbs. (8 kg)
Page 1
G24M
G24M2-75 G24M3(X)-75
75,000 (22.0)
61,700 (18.1)
80.1%
76.8%
4 (102)
45 - 75 (25 - 42)
9 x 7
229 x 178 254 x 178
1/4 (187)
1, 1-1/2 or 2 2, 2-1/2 or 3
3.5, 5.3 or7.0 7.0, 8.8 or 10.6
135 (61)
ã 1998 Lennox Industries Inc.
Litho U.S.A.
80.0%
76.8%
10 x 7
1/3 (224)