508297-01
Page 48 of 57
Issue 2219
Table 15.
Manifold and Supply Line Pressure 0-10,000 ft.
Capacity
Gas
Manifold Pressure in. w.g.
Supply Line Pressure
in. w.g.
0-10,000 ft.
0-4500 ft.
4501-5500 ft.
5501-6500 ft.
6501-7500 ft. 7501-10000 ft.
All Sizes
Natural
3.5
3.3
3.2
3.1
3.5
4.5
13.0
LP /
Propane
10.0
9.4
9.1
8.9
10.0
11.0
13.0
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.
High Altitude Information
NOTE:
In Canada, certification for installations at
elevations over 4500 feet (1371 m) is the jurisdiction of
local authorities.
Units may be installed at altitudes up to 10,000 ft. above
sea level. See Table 15 for de-rate manifold values. Units
installed at altitude of 7501 - 10,000 feet require an orifice
change. Units installed at altitudes of 4,501 - 10,000 feet
Capacity
0-7,500 ft
(0-2,286m)
7,501 - 10,000 ft
(2,286 - 3,048 m)
Natural to LP/Propane
High Altitude Natural Burner
Orifice Kit
High Altitude LP/Propane
Burner Orifice Kit
030
17H63
14C90
17H66
045
11K49
73W37
11K44
070
090
110
135
Pressure switch is factory set. No adjustment necessary. All models use the factory-installed pressure switch from 0-4500 feet (0-
1370 m).
Table 16.
Burner Orifice Conversion Kits at Varying Altitudes
Capacity
0 - 4500 ft
(0 - 1,371m)
4501 - 7500 ft
(1371 - 2286m)
7501 - 10000 ft
(2286 - 3048m)
030/045
No Change
11U66
11U69
070
No Change
11U70
11U68
090
No Change
11U70
11U64
110
No Change
11U70
135
No Change
11U70
11U68
Pressure switch is factory set. No adjustment necessary. All models use the factory-installed pressure switch from 0-4500 feet (0-
1371 m).
Table 17. Pressure Switch Requirements at Varying Altitudes
(1371 -3048 m) may require a pressure switch change
which can be ordered separately.
Table 16 and Table 17 list required pressure switch changes
and orifice conversion kits at varying altitudes.
The combustion air pressure switches are factory set and
require no adjustment.