Bryant Induced-Combustion 4-Way Multipoise 310AAV - Manual (Page 42)

If it becomes necessary to clean the heat exchangers because of
dust or corrosion, proceed as follows:
1. Turn OFF gas and electrical power to furnace.
2. Remove outer access door.
3. Disconnect vent connector from furnace vent elbow.
4. For downflow or horizontal furnace having an internal vent
pipe, remove internal vent pipe within the casing.
5. Disconnect wires to the following components. Mark wires to
aid in reconnection of (be careful when disconnecting wires
from switches because damage may occur):
a. Draft safeguard switch.
TABLE 13—Orifice Size* and Manifold Pressure For Gas Input Rate
(Tabulated Data Based On 21,000 Btuh Per Burner, Derated 4 Percent For Each 1000 Ft Above Sea Level)
ALTITUDE
RANGE
(FT)
AVG GAS
HEAT VALUE
(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.
and
Canada 0
to
2000
900 42 3.2 42 3.3 42 3.4 42 3.5
925 43 3.7 43 3.8 42 3.2 42 3.3
950 43 3.5 43 3.6 43 3.7 43 3.8
975 43 3.3 43 3.4 43 3.5 43 3.7
1000 44 3.6 43 3.3 43 3.4 43 3.5
1025 44 3.4 44 3.6 43 3.2 43 3.3
1050 44 3.3 44 3.4 44 3.5 43 3.2
1075 45 3.8 44 3.2 44 3.3 44 3.4
1100 46 3.8 45 3.7 44 3.2 44 3.3
ALTITUDE
RANGE
(FT)
AVG GAS
HEAT VALUE
(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.
and
Canada
U.S.A.
Altitudes
2001
to
3000
or
Canada
Altitudes
2000
to
4500
800 43 3.8 42 3.2 42 3.3 42 3.4
825 43 3.5 43 3.7 43 3.8 42 3.2
850 43 3.3 43 3.5 43 3.6 43 3.7
875 43 3.2 43 3.3 43 3.4 43 3.5
900 43 3.0 43 3.1 43 3.2 43 3.3
925 43 2.8 43 2.9 43 3.0 43 3.1
950 43 2.7 43 2.8 43 2.9 43 2.9
975 43 2.5 43 2.6 43 2.7 43 2.8
1000 43 2.4 43 2.5 43 2.6 43 2.7
ALTITUDE
RANGE
(FT)
AVG GAS
HEAT VALUE
(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
3001
to
4000
775 43 3.5 43 3.7 43 3.8 42 3.2
800 43 3.3 43 3.4 43 3.5 43 3.7
825 43 3.1 43 3.2 43 3.3 43 3.4
850 43 2.9 43 3.0 43 3.1 43 3.2
875 43 2.8 43 2.9 43 3.0 43 3.1
900 43 2.6 43 2.7 43 2.8 43 2.9
925 43 2.5 43 2.6 43 2.7 43 2.7
950 43 2.4 43 2.4 43 2.5 43 2.6
ALTITUDE
RANGE
(FT)
AVG GAS
HEAT VALUE
(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
4001
to
5000
750 43 3.3 43 3.4 43 3.5 43 3.6
775 43 3.1 43 3.2 43 3.3 43 3.4
800 43 2.9 43 3.0 43 3.1 43 3.2
825 43 2.7 43 2.8 43 2.9 43 3.0
850 43 2.6 43 2.7 43 2.8 43 2.8
875 43 2.4 43 2.5 43 2.6 43 2.7
900 43 2.3 43 2.4 43 2.5 43 2.5
925 43 2.2 43 2.2 43 2.3 43 2.4
* Orifice numbers 43 are factory installed
41