Lennox ML193UH Installation Instructions

Page 42
Proper Cumbustion
Furnace should operate minimum 15 minutes with correct
manifold pressure and gas ow rate before checking com-
bustion. Take combustion sample beyond the ue outlet
nd compare to the tables below.
TABLE 12
ML193 Unit
CO
2
Nat CO
2
LP
045
7.2 - 7.9 8.6 - 9.3
070
090
110
135
The maximum carbon monoxide reading should not exceed 100 pm.
High Altitude Information
NOTE - In Canada, certication for installations at eleva-
tions over 4500 feet (1372 m) is the jurisdiction of local
authorities.
Units may be installed at altitudes up to 10,000 ft. above
sea level. See table 13 for de-rate manifold values. Units
installed at altitude of 7501 - 10,000 feet require an orice
change. Units installed at altitude of 4501 - 10,000 feet
require a pressure switch change which can be ordered
separately. Table 14 lists conversion kit and pressure
switch requirements at varying altitudes.
The combustion air pressure switch is factory-set and re-
quires no adjustment.
NOTE - A natural to LP/propane gas changeover kit is
necessary to convert this unit. Refer to the changeover kit
installation instruction for the conversion procedure.
TABLE 13
Manifold and Supply Line Pressure 0-10,000ft.
ML193
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 - 7500 ft 7501 - 10,000 ft
All
Models
Natural 3.5 3.3 3.2 3.1 3.5 4.5 13.0
L.P. Propane 10.0 9.4 9.1 8.8 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.
TABLE 14
Conversion Kit and Pressure Switch Requirements at Varying Altitudes
ML193 Model
Natural to LP/
Propane
High Altitude
Natural Burner
Orice Kit
LP/Propane to
Natural
High Altitude LP/
Propane Burner
Orice Kit
High Altitude Pressure Switch
0 - 7500 ft
(0 - 2286m)
7501 - 10,000 ft
(2286 - 3038m)
0 - 7500 ft
(0 - 2286m)
7501 - 10,000 ft
(2286 - 3038m)
4501 - 7500 ft
(1373 - 2286m)
7501 -10,000 ft
(2286 - 3048m)
-045
*11K49 73W37 *73W81 *11K44
11U65 11U66
-070
-090
-110
-135 11U70 11U68
* 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).

Lennox ML193UH Specifications

General

Brand	Lennox
Model	ML193UH
Category	Furnace
Language	English