Table 8—Model 58RAV Orifice Size† and Manifold Pressure for Correct Input
(Continued)
(Tabulated Data Based on 23,000 BTUH Per Burner, Derated 4 Percent per 1000 Ft Above Sea Level)*
ALTITUDE
RANGE
(FT)
AVG GAS
HEAT VALUE
AT ALTITUDE
(BTU/CU FT)
SPECIFIC GRAVITY OF NATURAL GAS
0.58
0.60
0.62
0.64
0.66
Orifice
No.
Manifold
Pressure
Orifice
No.
Manifold
Pressure
Orifice
No.
Manifold
Pressure
Orifice
No.
Manifold
Pressure
Orifice
No.
Manifold
Pressure
U.S.A.
Only
700
43
3.7
43
3.8
42
3.2
42
3.3
42
3.4
725
43
3.4
43
3.6
43
3.7
43
3.8
42
3.2
750
43
3.2
43
3.3
43
3.4
43
3.5
43
3.6
775
43
3.0
43
3.1
43
3.2
43
3.3
43
3.4
5001
800
43
2.8
43
2.9
43
3.0
43
3.1
43
3.2
825
43
2.7
43
2.7
43
2.8
43
2.9
43
3.0
to
850
43
2.5
43
2.6
43
2.7
43
2.8
43
2.8
875
43
2.4
43
2.4
43
2.5
43
2.6
43
2.7
6000
900
43
2.2
43
2.3
43
2.4
43
2.5
43
2.5
925
43
2.1
43
2.2
43
2.3
43
2.3
43
2.4
950
48
3.8
43
2.1
43
2.1
43
2.2
43
2.3
975
48
3.6
48
3.7
43
2.0
43
2.1
43
2.2
1000
48
3.4
48
3.5
48
3.6
48
3.7
43
2.1
ALTITUDE
RANGE
(FT)
AVG GAS
HEAT VALUE
AT ALTITUDE
(BTU/CU FT)
SPECIFIC GRAVITY OF NATURAL GAS
0.58
0.60
0.62
0.64
0.66
Orifice
No.
Manifold
Pressure
Orifice
No.
Manifold
Pressure
Orifice
No.
Manifold
Pressure
Orifice
No.
Manifold
Pressure
Orifice
No.
Manifold
Pressure
U.S.A.
Only
650
43
3.7
43
3.8
42
3.2
42
3.3
42
3.5
675
43
3.4
43
3.5
43
3.7
43
3.8
42
3.2
700
43
3.2
43
3.3
43
3.4
43
3.5
43
3.6
6001
725
43
3.0
43
3.1
43
3.2
43
3.3
43
3.4
750
43
2.8
43
2.9
43
3.0
43
3.1
43
3.2
to
775
43
2.6
43
2.7
43
2.8
43
2.9
43
3.0
800
43
2.4
43
2.5
43
2.6
43
2.7
43
2.8
7000
825
43
2.3
43
2.4
43
2.5
43
2.5
43
2.6
850
43
2.2
43
2.2
43
2.3
43
2.4
43
2.5
875
43
2.0
43
2.1
43
2.2
43
2.3
43
2.3
ALTITUDE
RANGE
(FT)
AVG GAS
HEAT VALUE
AT ALTITUDE
(BTU/CU FT)
SPECIFIC GRAVITY OF NATURAL GAS
0.58
0.60
0.62
0.64
0.66
Orifice
No.
Manifold
Pressure
Orifice
No.
Manifold
Pressure
Orifice
No.
Manifold
Pressure
Orifice
No.
Manifold
Pressure
Orifice
No.
Manifold
Pressure
U.S.A.
Only
625
43
3.4
43
3.6
43
3.7
43
3.8
42
3.2
650
43
3.2
43
3.3
43
3.4
43
3.5
43
3.6
675
43
3.0
43
3.1
43
3.2
43
3.3
43
3.4
7001
700
43
2.7
43
2.8
43
2.9
43
3.0
43
3.1
725
43
2.6
43
2.6
43
2.7
43
2.8
43
2.9
to
750
43
2.4
43
2.5
43
2.6
43
2.6
43
2.7
775
43
2.2
43
2.3
43
2.4
43
2.5
43
2.5
8000
800
43
2.1
43
2.2
43
2.2
43
2.3
43
2.4
825
48
3.7
43
2.0
43
2.1
43
2.2
43
2.2
850
48
3.5
48
3.6
48
3.7
43
2.1
43
2.1
ALTITUDE
RANGE
(FT)
AVG GAS
HEAT VALUE
AT ALTITUDE
(BTU/CU FT)
SPECIFIC GRAVITY OF NATURAL GAS
0.58
0.60
0.62
0.64
0.66
Orifice
No.
Manifold
Pressure
Orifice
No.
Manifold
Pressure
Orifice
No.
Manifold
Pressure
Orifice
No.
Manifold
Pressure
Orifice
No.
Manifold
Pressure
U.S.A.
Only
600
43
3.2
43
3.3
43
3.4
43
3.5
43
3.6
625
43
3.0
43
3.1
43
3.2
43
3.3
43
3.4
8001
650
43
2.7
43
2.8
43
2.9
43
3.0
43
3.1
675
43
2.5
43
2.6
43
2.7
43
2.8
43
2.9
to
700
43
2.4
43
2.4
43
2.5
43
2.6
43
2.7
725
43
2.2
43
2.3
43
2.3
43
2.4
43
2.5
9000
750
43
2.0
43
2.1
43
2.2
43
2.3
43
2.3
775
48
3.6
48
3.7
43
2.1
43
2.1
43
2.2
800
48
3.4
48
3.5
48
3.6
48
3.7
43
2.0
* For size 135-20 only, input is 22,500 Btuh per burner. Deduct 0.1-in. wc from manifold pressure shown in table. Change orifice size if manifold pressure falls below
3.2-in. wc on altitudes up to 2000 ft, otherwise change orifice size if manifold pressure falls below 2.0-in. wc.
† Orifice sizes shown in BOLD are factory installed.
17