Carrier 58MXA Installation, Start-Up, And Operating Instructions Manual page 42

Table 9—Model 58MXA Orifice Size and Manifold Pressure for Correct Input
(Tabulated Data Based on 20,000 Btuh per Burner, Derated 2% for Each 1000 Ft Above Sea Level) *
AVG GAS
ALTITUDE
HEAT VALUE
RANGE
AT ALTITUDE
(FT)
(BTU/CU FT)
625
650
675
7001 700
725
to 750
775
8000 800
825
850
AVG GAS
ALTITUDE
HEAT VALUE
RANGE
AT ALTITUDE
(FT)
(BTU/CU FT)
600
625
8001 650
675
to 700
725
9000 750
775
800
AVG GAS
ALTITUDE
HEAT VALUE
RANGE
AT ALTITUDE
(FT)
(BTU/CU FT)
575
600
9001 625
650
to 675
700
10,000 725
750
775
Orifice numbers 45 shown in BOLD are factory installed.
Station or Dealer. To determine correct input rate for
altitude, see example above and use 0.95 as derate multi-
plier factor.
→
b. Reinstall burner box cover.
→
c. Gas valve regulator seal MUST be on.
d. Turn off all other gas appliances and pilots.
e. Start furnace and let operate for 3 minutes.
f. Measure time (in sec) for gas meter test dial 1 revolution.
g. Refer to Table 12 for cu ft of gas per hr.
h. Multiply gas rate (cu ft/hr) X heating value (Btu/cu ft)
using natural gas heating value from local gas
utility/supplier.
For Use with 040 through 120 Size Furnaces Only
0.58 0.60
Orifice Manifold Orifice
No. Pressure No.
43 3.8 42
43 3.5 43
44 3.8 43
44 3.5 44
44 3.3 44
45 3.7 45
45 3.5 45
45 3.3 45
45 3.1 45
45 2.9 45
0.58 0.60
Orifice Manifold Orifice
No. Pressure No.
43 3.8 42
43 3.5 43
44 3.7 43
44 3.5 44
44 3.2 44
45 3.6 45
45 3.4 45
45 3.2 45
45 3.0 45
0.58 0.60
Orifice Manifold Orifice
No. Pressure No.
43 3.8 42
43 3.5 43
44 3.7 44
44 3.4 44
45 3.8 44
45 3.6 45
45 3.3 45
45 3.1 45
45 2.9 45
SPECIFIC GRAVITY OF NATURAL GAS
0.62
Manifold Orifice Manifold
Pressure No. Pressure
3.3 42 3.4
3.7 43 3.8
3.4 43 3.5
3.6 44 3.8
3.4 44 3.5
3.8 44 3.3
3.6 45 3.7
3.4 45 3.5
3.2 45 3.3
3.0 45 3.1
SPECIFIC GRAVITY OF NATURAL GAS
0.62
Manifold Orifice Manifold
Pressure No. Pressure
3.3 42 3.4
3.6 43 3.8
3.4 43 3.5
3.6 44 3.7
3.3 44 3.4
3.8 44 3.2
3.5 45 3.6
3.3 45 3.4
3.1 45 3.2
SPECIFIC GRAVITY OF NATURAL GAS
0.62
Manifold Orifice Manifold
Pressure No. Pressure
3.2 42 3.3
3.6 43 3.7
3.8 43 3.5
3.5 44 3.7
3.3 44 3.4
3.7 45 3.8
3.4 45 3.6
3.2 45 3.3
3.0 45 3.1
42
(Continued)
0.64 0.66
Orifice Manifold Orifice
No. Pressure No.
42 3.5 42
42 3.2 42
43 3.6 43
43 3.4 43
44 3.6 44
44 3.4 44
45 3.8 44
45 3.6 45
45 3.4 45
45 3.2 45
0.64 0.66
Orifice Manifold Orifice
No. Pressure No.
42 3.5 42
42 3.2 42
43 3.6 43
44 3.8 43
44 3.6 44
44 3.3 44
45 3.8 44
45 3.5 45
45 3.3 45
0.64 0.66
Orifice Manifold Orifice
No. Pressure No.
42 3.5 42
42 3.2 42
43 3.6 43
44 3.8 43
44 3.5 44
44 3.3 44
45 3.7 45
45 3.4 45
45 3.2 45
Manifold
Pressure
3.6
3.3
3.7
3.5
3.7
3.5
3.3
3.7
3.5
3.3
Manifold
Pressure
3.6
3.3
3.7
3.4
3.7
3.4
3.2
3.6
3.4
Manifold
Pressure
3.6
3.3
3.7
3.4
3.6
3.4
3.8
3.5
3.3