28
■
Install a
¹⁄₈
" NPT pipe plug fitting, accessible for test gage
connection, immediately upstream of the gas supply
connection to the furnace.
■
Always use a backup wrench when making the connection to
the gas control valve to keep it from turning.
NOTE: The orientation of the gas control valve on the
manifold must be maintained as shipped from the factory.
■
Maximum torque for the gas control valve connection is
375 in-lbs.
NOTE: Excessive overtightening may damage the gas control
valve.
■
Install a manual shutoff valve between the gas meter and the
furnace within 6 ft (1.8 m) of the furnace.
■
If a union is installed, the union must be downstream of the
manual shutoff valve, between the shutoff valve and the
furnace.
■
Tighten all joints securely.
■
Connect the furnace to the building piping by one of the
following methods:
1. Rigid metallic pipe and fittings.
2. Semirigid metallic tubing and metallic fittings.
NOTE: Aluminum alloy tubing must not be used in exterior
locations. In order to seal the grommet cabinet penetration,
rigid pipe must be used to reach the outside of the cabinet. A
semirigid connector to the gas piping may be used from
there.
■
Use listed gas appliance connectors in accordance with their
instructions.
■
Gas connectors must be fully in the same room as the
furnace.
■
Protect gas connectors and semirigid tubing against physical
and thermal damage when installed.
■
Ensure aluminum alloy tubing and connectors are coated to
protect against external corrosion when in contact with
masonry, plaster, insulation or subjected to repeated wetting
by liquids such as water (except rain water), detergents or
sewage.
Gas Piping Connections—Upflow
Gas Piping Connections—Counterflow
Gas Piping Connections—Horizontal Upflow
A. Alternate gas line location
B. Manifold
C. Gas control valve
D. Burners
E. Manual shutoff valve (upstream
from ground joint pipe union)
F. Height required by local codes
G. Drip leg
H. Grommet in standard gas line hole
I. Ground joint pipe union
J. Plug in alternate gas line hole
A
B
C
D
E
G
H
I
J
F
A. Manual shutoff valve (upstream
from ground joint pipe union)
B. Alternate gas line location
C. Plug in alternate gas line hole
D. Gas control valve
E. Manifold
F. Burners
G. Ground joint pipe union
H. Grommet in standard gas line hole
I. Drip leg
J. Height required by local codes
A. Gas control valve
B. Ground joint pipe union
C. Manual shutoff valve (upstream
from ground joint pipe union)
D. Drip leg
E. Grommet in standard gas line hole
F. Drain trap
G. Plug in alternate gas line hole
H. Alternate gas line location
I. Manifold
J. Burners
A
B
C
D
E
F
G
H
I
J
C
D
E
B
A
I
H
G
F
J
