Carrier 58CTA, Installation And Service Instructions Manual, Page: 42 / 58

Table 13–Orifice Size and Manifold Pressure for Gas Input Rate
(Tabulated Data Based On 22,000 Btuh High-Heat/14,500 Btuh for Low-Heat Per Burner,
Derated 4 Percent For Each 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
Orifice
No.
Manifold
Pressure
Orifice
No.
Manifold
Pressure
Orifice
No.
Manifold
Pressure
Orifice
No.
Manifold
Pressure
U.S.A.
Only
5001
to
6000
725 43 3.4/1.5 43 3.5/1.5 43 3.6/1.6 43 3.7/1.6
750 43 3.2/1.4 43 3.3/1.4 43 3.4/1.5 43 3.5/1.5
775 44 3.4/1.5 44 3.5/1.5 43 3.2/1.4 43 3.3/1.4
800 44 3.2/1.4 44 3.3/1.4 44 3.4/1.5 44 3.5/1.5
825 46 3.8/1.7 45 3.8/1.6 44 3.2/1.4 44 3.3/1.4
850 46 3.6/1.6 46 3.7/1.6 46 3.8/1.7 45 3.8/1.6
875 47 3.8/1.7 46 3.5/1.5 46 3.6/1.6 46 3.7/1.6
900 47 3.6/1.6 47 3.8/1.6 46 3.4/1.5 46 3.5/1.5
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
Orifice
No.
Manifold
Pressure
Orifice
No.
Manifold
Pressure
Orifice
No.
Manifold
Pressure
Orifice
No.
Manifold
Pressure
U.S.A.
Only
6001
to
7000
675 43 3.4/1.5 43 3.5/1.5 43 3.6/1.6 43 3.7/1.6
700 44 3.6/1.6 43 3.3/1.4 43 3.4/1.5 43 3.5/1.5
725 44 3.4/1.5 44 3.5/1.5 44 3.6/1.6 43 3.2/1.4
750 45 3.8/1.7 44 3.3/1.4 44 3.4/1.5 44 3.5/1.5
775 46 3.7/1.6 45 3.7/1.6 45 3.8/1.7 44 3.2/1.4
800 46 3.5/1.5 46 3.6/1.6 46 3.8/1.6 45 3.7/1.6
825 47 3.7/1.6 46 3.4/1.5 46 3.5/1.5 46 3.6/1.6
850 47 3.5/1.5 47 3.6/1.6 47 3.8/1.6 46 3.4/1.5
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
Orifice
No.
Mainifold
Pressure Orifice
No.
Manifold
Pressure
Orifice
No.
Manifold
Pressure
Orifice
No.
Manifold
Pressure
U.S.A.
Only
7001
to
8000
650 44 3.6/1.6 43 3.2/1.4 43 3.4/1.5 43 3.5/1.5
675 44 3.3/1.5 44 3.5/1.5 44 3.6/1.6 43 3.2/1.4
700 45 3.8/1.6 44 3.2/1.4 44 3.3/1.4 44 3.4/1.5
725 46 3.7/1.6 46 3.8/1.7 45 3.7/1.6 44 3.2/1.4
750 46 3.4/1.5 46 3.6/1.5 46 3.7/1.6 46 3.8/1.6
775 47 3.6/1.6 47 3.8/1.6 46 3.4/1.5 46 3.6/1.5
800 47 3.4/1.5 47 3.5/1.5 47 3.7/1.6 47 3.8/1.6
825 48 3.7/1.6 48 3.8/1.6 47 3.4/1.5 47 3.6/1.5
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
Orifice
No.
Manifold
Pressure
Orifice
No.
Manifold
Pressure
Orifice
No.
Manifold
Pressure
Orifice
No.
Manifold
Pressure
U.S.A.
Only
8001
to
9000
625 44 3.3/1.5 44 3.5/1.5 44 3.6/1.6 43 3.2/1.4
650 45 3.7/1.6 44 3.2/1.4 44 3.3/1.4 44 3.4/1.5
675 46 3.6/1.6 46 3.8/1.6 45 3.7/1.6 45 3.8/1.7
700 47 3.8/1.7 46 3.5/1.5 46 3.6/1.6 46 3.7/1.6
725 47 3.6/1.6 47 3.7/1.6 47 3.8/1.7 46 3.5/1.5
750 48 3.8/1.7 47 3.5/1.5 47 3.6/1.6 47 3.7/1.6
775 48 3.6/1.5 48 3.7/1.6 48 3.8/1.7 47 3.5/1.5
* Orifice numbers 43 are factory installed
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