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1995 Lennox Industries Inc.
LITHO U.S.A.
Corp. 9505–L2
G25MV
Service Literature
G25MV SERIES UNITS
G25MV series units are mid–efficiency gas furnaces
manufactured with tubular steel heat exchangers
formed of aluminized steel. G25MV units are available
in heating capacities of 60,000 to 120,000 Btuh (17.6 to
35.2 kW) and cooling applications from 1.5 through 5
tons (3.5 through 17.6 kW). Refer to Engineering Hand-
book for proper sizing.
Units are factory equipped for use with natural gas. All
G25MV units use a hot surface ignition system. The
G25MV units meet the California Nitrogen Oxides (NO
x
)
Standards and California Seasonal Efficiency require-
ments. All units use a two stage gas valve along with a
two stage induced draft blower assembly. The gas valve
is redundant to assure safety shut–off as required by
A.G.A. or C.G.A.
All G25MV units are equipped with an electronic vari-
able speed (VSM) fan motor. The VSM motor maintains
a specified air volume throughout the entire external
static range.
Units may be installed in upflow, downflow or horizon-
tal position. The heat exchanger is designed for upright
or horizontal use only. When the unit is installed in the
downflow position, the heat exchanger is field re-
moved 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 sim-
ply disconnecting gas, unplugging wiring harnesses
and removing four screws holding the heat exchanger in
place. The heat exchanger slides out of the cabinet.
Information contained in this manual is intended for use
by Lennox service technicians only. All specifications
are subject to change. Procedures outlined in this manu-
al are presented as a recommendation only and do not
supersede or replace local or state codes.
G25MV
