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27
OPERATION (continued)
Table 7A
High Altitude Deration - United States
Altitude
Manifold Pressure
BTU Output
1
Natural Gas
2
Liquid Propane
3
Feet
Meters
Inches W.C.
Pa
Inches W.C.
Pa
Percentage
0-2,000
0-610
3.5
872
10.0
2491
100%
2,001-3,000
611-915
3.2
797
9.2
2292
96%
3,001-4,000
916-1220
2.9
722
8.4
2092
92%
4,001-5,000
1221-1525
2.7
673
7.7
1918
88%
5,001-6,000
1526-1830
2.4
598
7.0
1744
84%
6,001-7,000
1831-2135
2.2
548
6.4
1594
80%
7001-8000
2136-2440
2.0
498
5.7
1420
76%
8001-9000
2441-2745
1.8
448
5.1
1270
72%
9001-10,000
2746-3045
1.6
399
4.6
1145
68%
Notes: 1. Deration based on ANSI Z223.1 (NFPA 54).
2. Table based on heating value of 1,050 BTU/Cu. feet at sea level.
3. Table based on heating value of 2,500 BTU/Cu. feet at sea level.
4. Consult local utility for actual heating value.
High Altitude Deration - Canada
Altitude
Manifold Pressure
BTU Output
1
Natural Gas
2
Liquid Propane
3
Feet
Meters
Inches W.C.
Pa
Inches W.C.
Pa
Percentage
0-2,000
0-610
3.5
872
10.0
2491
100%
2001-3000
611-915
3.2
797
9.2
2292
96%
3001-4000
916-1220
2.9
722
8.4
2092
92%
4001-4500
1221-1371
2.8
697
7.9
1968
90%
Notes: 1. Deration based on CGA 2.17-M91
2. Table based on heating value of 1,050 BTU/Cu. feet at sea level.
3. Table based on heating value of 2,500 BTU/Cu. feet at sea level.
4. Consult local utility for actual heating value.