Lennox ML296UHV Series User Manual

Page 45
NOTE- To obtain accurate reading, shut off all other gas
appliances connected to meter.
TABLE 18
GAS METER CLOCKING CHART
ML296
Unit
Seconds for One Revolution
Natural LP
1 cu ft
Dial
2 cu ft
Dial
1 cu ft
Dial
2 cu ft
DIAL
-045 80 160 200 400
-70 55 110 136 272
-90 41 82 102 204
-110 27 54 68 136
Natural-1000 btu/cu ft LP-2500 btu/cu ft
IMPORTANT
For safety, shut unit off and remove manometer as
soon as an accurate reading has been obtained.
Take care to replace pressure tap plug.
G- Proper Combustion
Furnace should operate minimum 15 minutes with correct
manifold pressure and gas flow rate before checking com
bustion. See sections E- and F-. Take combustion sample
beyond the flue outlet. Table 19 shows acceptable com
bustions. The maximum carbon monoxide reading
should not exceed 100 ppm.
TABLE 19
EL296
Model
CO
2
%
For Nat
CO
2
%
For L.P
Low Fire High Fire Low Fire High Fire
045 5.4 - 6.4 7.5 - 8.5 6.4 - 7.4 8.8 - 9.8
070 5.3 - 6.3 7.4 - 8.4 6.3 - 7.3 8.7 - 9.7
090 5.8 - 6.8 7.6 - 8.6 6.8 - 7.8 8.9 - 9.9
110 6.1 - 7.1 8.0 - 9.0 7.1 - 8.1 9.3 - 10.3
The maximum carbon monoxide reading should not exceed 100ppm.
H- High Altitude
The manifold pressure, gas orifice and pressure switch
may require adjustment or replacement to ensure proper
operation at higher altitudes. See table 20 for gas conver
sion and pressure switch kits. See table 21 for manifold
pressures
TABLE 20
LP/Propane Conversion Kit and Pressure Switch Requirements at Varying Altitudes
ML296
Unit
Natural to
LP/Propane
High Altitude
Natural Burner
Orifice Kit
High Altitude
LP/Propane Burner
Orifice Kit
High Altitude Pressure Switch
0 - 7500 ft
(0 - 2286m)
7501 - 10,000 ft
(2286 - 3038m)
7501 - 10,000 ft
(2286 - 3038m)
4501 - 7500 ft
(1373 - 2286m)
7501 -10,000 ft
(2286 - 3048m)
-045
*11K51 73W37 *11K46
14A47 14A50
-070 14A54 14A53
-090 14A57 14A54
-110 14A46 14A51
* Conversion requires installation of a gas valve manifold spring which is provided with the gas conversion kit.
Pressure switch is factory set. No adjustment necessary. All models use the factory-installed pressure switch from 0-4500 feet (0-1370 m).
TABLE 21
Manifold Pressure Settings
ML296
Unit
Gas
Manifold Pressure in. wg.
Supply Line
Pressure
in. w.g.
0 - 10000 ft.
0-4500 ft. 4501-5500 ft. 5501-6500 ft. 6501 - 7500ft. 7501 - 10000ft.
Low
Fire
High
Fire
Low
Fire
High
Fire
Low
Fire
High
Fire
Low
Fire
High
Fire
Low
Fire
High
Fire
Min Max
All
Sizes
Natural 1.7 3.5 1.6 3.3 1.5 3.2 1.5 3.1 1.7 3.5 4.5 13.0
LP/
propane
4.9 10.0 4.6 9.4 4.4 9.1 4.3 8.9 4.9 10.0 11.0 13.0
NOTE - A natural to L.P. propane gas changeover kit is necessary to convert this unit. Refer to the changeover kit installation instruction for the conversion
procedure.

Lennox ML296UHV Series Specifications

General

Brand	Lennox
Model	ML296UHV Series
Category	Furnace
Language	English