Operating instructions
Table 10--Model 58MXA Orifice Size and Manifold Pressure for Correct Input
For Use with 140 Size Furnaces Only
(Tabulated Data Based on 23,000 Btuh per Burner, Derated 2% for Each 1000 Ft Above Sea Level) *
ALTITUDE
RANGE
(FT)
0
O
to
2000
D
0%
derate
ALTITUDE
RANGE
(ft)
U,S,A,
Altitudes
2001 to
3000 or
_ Canada
Altitudes
200t to
4500
5%
derate
ALTITUDE
RANGE
(ft)
___ 3001
O
_ to
D 4000
7%
derate
AVG GAS
HEAT VALUE
AT ALTITUDE
(BTU/CU FT)
850
875
900
925
950
975
1000
1025
1050
1075
1100
AVG GAS
HEAT VALUE
AT ALTITUDE
(Btu/cu if)
775
800
825
850
875
900
925
950
975
1000
1025
AVG GAS
HEAT VALUE
AT ALTITUDE
(Btu/cu if)
750
775
800
825
850
875
900
925
950
975
1000
SPECIFIC GRAVITY OF NATURAL GAS
0,58 0.50 0.52
Orifice Mani_ld Orifice Mani_ld Orifice Manifold
No. Pressure No. Pressure No. Pressure
41 3.6 4! 3.7 41 3.8
42 3.8 4! 3.5 41 3.6
42 3.5 42 3.7 42 3.8
42 3.4 42 3.5 42 3.6
42 3.2 42 3.3 42 3.4
43 3.7 43 3.8 42 3.2
43 3.5 43 3.6 43 3.7
43 3.3 43 3.4 43 3.6
43 3.2 43 3.3 43 3.4
44 3.5 44 3.6 43 3.2
44 3.3 44 3.4 44 3.5
0.64 0,66
Orifice Manifold Orifice Manifold
No. Pressure No. Pressure
40 3.6 40 3.8
41 3.7 41 3.8
41 3.5 41 3.6
42 3.7 42 3.8
42 3.5 42 3.6
42 3.3 42 3.4
42 3.2 42 3.3
43 3.7 43 3,8
43 3,5 43 3.6
43 3,3 43 3.4
43 3.2 43 3,3
SPECIFIC GRAVITY OF NATURAL GAS
0.58 0.50 0.52
Orifice Manifold Orifice Manifold Orifice Manifold
No. Pressure No. Pressure No. Pressure
41 3.7 41 3.8 40 3.6
42 3.8 4! 3.6 41 3.7
42 3.6 42 3.7 41 3.5
42 3.4 42 3.5 42 3.6
42 3.2 42 3.3 42 3.4
43 3.7 43 3.8 42 3.2
43 3.5 43 3.6 43 3.7
43 3.3 43 3.4 43 3.5
43 3.1 43 3.3 43 3.4
43 3.0 43 3.1 43 3.2
43 2.8 43 2.9 43 3.0
0.54 0.65
Orifice Manifold Orifice Manifold
No. Pressure No. Pressure
40 3.7 39 3.6
41 3.8 40 3.6
41 3.6 41 3.7
42 3.7 41 3.5
42 3.5 42 3.6
42 3.3 42 3.4
42 3.2 42 3.3
43 3.7 43 3.8
43 3,5 43 3.5
43 3,3 43 3,4
43 3,1 43 3,2
SPECIFIC GRAVITY OF NATURAL GAS
0.58 0.50 0.52
Orifice Mani_ld Orifice Mani_ld Orifice Manifold
No. Pressure No. Pressure No. Pressure
41 3.6 41 3.8 40 3.6
42 3.8 41 3.5 41 3.6
42 3.5 42 3.7 42 3.8
42 3.3 42 3.4 42 3.6
43 3.8 42 3.2 42 3.4
43 3.5 43 3.7 42 3.2
43 3.4 43 3.5 43 3.6
43 3.2 43 3.3 43 3.5
43 3.1 43 3.2 43 3.3
43 2.9 43 3.0 43 3.1
43 2.8 43 2.9 43 3.0
0.54 0,66
Orifice Manifold Orifice Manifold
No. Pressure No. Pressure
40 3.7 40 3.8
41 3.7 40 3.6
41 3.5 41 3.6
42 3.7 42 3.8
42 3.5 42 3.6
42 3.3 42 3.4
43 3,8 42 3.2
43 3.5 43 3,7
43 3,4 43 3.5
43 3.2 43 3.3
43 3.0 43 3.1
* Orifice numbers 43 shown in BOLD are factory installed.
Percents of derate are based on midpoints of U.S. altitude ranges.
44