37
Table 8. High Altitude Deration – Propane Gas
HIGH ALTITUDE DERATION – PROPANE GAS
ALTITUDE ABOVE
SEA LEVEL
INPUT (BTU)
38,000
(SC MODELS)
38,000
(SD MODELS)
54,000
72,000
90,000
108,000 118,000 120,000
0 to 1,999 FT
56
60
56
56
56
56
55
55
ORIFICE SIZE
10.0
10.0
10.0
10.0
10.0
10.0
10.0
10.0
MANIFOLD PRESSURE
2,000 to 2,999 FT
56
60
56
56
56
56
55
55
ORIFICE SIZE
9.0
9.0
9.0
9.0
9.0
9.0
9.0
9.0
MANIFOLD PRESSURE
3,000 to 4,999 FT
56
60
56
56
56
56
55
55
ORIFICE SIZE
8.5
8.5
8.5
8.5
8.5
8.5
8.5
8.5
MANIFOLD PRESSURE
5,000 to 5,999 FT
57
61
57
57
57
57
56
56
ORIFICE SIZE
10.0
8.5
10.0
10.0
10.0
10.0
10.0
10.0
MANIFOLD PRESSURE
6,000 to 7,999 FT
57
61
57
57
57
57
56
56
ORIFICE SIZE
9.0
8.0
9.0
9.0
9.0
9.0
9.0
9.0
MANIFOLD PRESSURE
8,000 to 10,000 FT
57
61
57
57
57
57
56
56
ORIFICE SIZE
8.5
7.5
8.5
8.5
8.5
8.5
8.5
8.5
MANIFOLD PRESSURE
LOCAL HEATING VALUES FOR NATURAL GAS
ALTITUDE ABOVE
SEA LEVEL
BTU PER CUBIC FOOT
650
700
750
800
850
900
950
1,000
1,050
2,000 FT
LOW
LOW
LOW
LOW
LOW
LOW
HIGH
HIGH
HIGH
3,000 FT
LOW
LOW
LOW
LOW
LOW
LOW
HIGH
HIGH
HIGH
4,000 FT
LOW
LOW
LOW
LOW
LOW
HIGH
HIGH
HIGH
HIGH
5,000 FT
LOW
LOW
LOW
LOW
LOW
HIGH
HIGH
HIGH
HIGH
6,000 FT
LOW
LOW
LOW
LOW
HIGH
HIGH
HIGH
HIGH
HIGH
7,000 FT
LOW
LOW
LOW
LOW
HIGH
HIGH
HIGH
HIGH
HIGH
8,000 FT
LOW
LOW
LOW
HIGH
HIGH
HIGH
HIGH
HIGH
HIGH
9,000 FT
LOW
LOW
LOW
HIGH
HIGH
HIGH
HIGH
HIGH
HIGH
10,000 FT
LOW
LOW
HIGH
HIGH
HIGH
HIGH
HIGH
HIGH
HIGH
Table 9. Natural Gas Heating Values