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E-Proper Combustion
Furnace should operate minimum 15 minutes with correct
manifold pressure and gas flow rate before checking com
-
bustion. Take combustion sample beyond the flue outlet
and compare to TABLE 18.
TABLE 18
ML193 Unit
CO
2
Nat
CO
2
LP
030
6.5 - 7.5
7.5 - 8.5
045
7.0 - 9.0
8.0 - 10.0
070
090
110
The maximum carbon monoxide reading should not exceed 100 pm.
F-High Altitude
NOTE -
In Canada, certification 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 19 for de-rate manifold values.
Units installed at altitude of 7501 - 10,000 feet require an
orifice change. Units installed at altitude of 4501 - 10,000
feet require a pressure switch change which can be or
-
dered separately.
TABLE 20 lists conversion kit and pressure switch require
-
ments 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 19
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
8.9
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.
TABLE 20
Conversion Kit and Pressure Switch Requirements at Varying Altitudes
ML193 Model
Natural to LP/
Propane
High Altitude
Natural Burner
Orifice Kit
LP/Propane to
Natural
High Altitude LP/
Propane Burner
Orifice 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)
-030
17H63
14C90
N/A
17H66
11U65
11U66
-045
*11K49
73W37
*73W81
*11K44
-070
-090
-110
* 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).
