Operating instructions
Table 9--Model 58MXA Orifice Size and Manifold Pressure for Correct Input
For Use with 040 through 120 Size Furnaces Only
(Tabulated Data is Based on 20,000 Btuh per Burner, Derated 2% for Each 1000 Ft Above Sea Level) *
ALTITUDE
RANGE
(FT)
r_
0
r_
(3
"u to
r_
2000
0%
derate
ALTITUDE
RANGE
(Ft)
U,S,A,
Altitudes
2001 to
"o
3000
or
Canada
Altitudes
_. 2001 to
4500
5%
derate
ALTITUDE
RANGE
(Ft)
___ 3001
O
_ to
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 0.60 0.62 0.64 0,66
Orifice Manifold Orifice Manifold Orifice Manifold Orifice Manifold Orifice Manifold
No. Pressure No. Pressure No. Pressure No. Pressure No. Pressure
43 3.7 43 3.8 42 3.2 42 3.3 42 3.4
43 3.5 43 3.6 43 3.7 43 3.8 42 3.2
44 3.7 43 3.4 43 3.5 43 3.6 43 3.7
44 3.5 44 3.7 44 3.8 43 3.4 43 3.5
44 3.4 44 3.5 44 3.6 44 3.7 44 3.8
44 3.2 44 3.3 44 3.4 44 3.5 44 3.6
45 3,7 45 3,8 44 3.2 44 3.4 44 3.5
45 3.5 45 3.6 45 3.7 44 3.2 44 3.3
45 3,3 45 3,4 45 3,6 45 3,7 45 3,8
45 3.2 45 3.3 45 3,4 45 3,5 45 3,6
47 3.6 47 3.7 45 3.2 45 3.4 45 3.5
SPECIFIC GRAVITY OF NATURAL GAS
0.58 0.60 0,62 0.64 0.66
Orifice Manifold Orifice Manifold Orifice Manifold Orifice Manifold Orifice Manifold
No. Pressure No. Pressure No. Pressure No. Pressure No. Pressure
43 3.8 42 3.2 42 3.3 42 3.4 42 3.5
43 3.5 43 3.7 43 3.8 42 3.2 42 3.3
44 3.8 43 3.4 43 3.6 43 3.7 43 3.8
44 3.6 44 3.7 44 3.8 43 3.5 43 3.6
44 3.4 44 3.5 44 3.6 44 3.7 43 3.4
44 3.2 44 3.3 44 3.4 44 3.5 44 3.6
45 3,7 45 3,8 44 3.2 44 3.3 44 3.4
45 3,5 45 3,6 45 3,7 45 3,8 44 3.3
45 3.3 45 3.4 45 3.5 45 3.6 45 3.8
45 3,1 45 3,2 45 3,4 45 3,5 45 3,6
45 3.0 45 3.1 45 3.2 45 3.3 45 3.4
SPECIFIC GRAVITY OF NATURAL GAS
0.58 0.60 0.62 0.64 0,66
Orifice Manifold Orifice Manifold Orifice Manifold Orifice Manifold Orifice Manifold
No. Pressure No. Pressure No. Pressure No. Pressure No. Pressure
43 3.7 43 3.8 42 3.3 42 3.4 42 3.5
43 3.5 43 3.6 43 3.7 43 3.8 42 3.2
44 3.7 43 3.4 43 3.5 43 3.6 43 3.7
44 3.5 44 3.6 44 3.8 43 3.4 43 3.5
44 3.3 44 3.4 44 3.5 44 3.7 44 3.8
45 3,8 44 3.2 44 3.3 44 3.5 44 3.6
45 3,6 45 3,7 45 3,8 44 3.3 44 3.4
45 3,4 45 3,5 45 3,6 45 3,7 44 3.2
45 3,2 45 3,3 45 3,4 45 3,5 45 3,7
45 3,0 45 3,2 45 3,3 45 3,4 45 3,5
45 2.9 45 3.0 45 3.1 45 3.2 45 3.3
* Orifice numbers 45 shown in BOLD are factory installed
Percents of derate are based on midpoints of U.S. altitude ranges
4!