Goodman GDVC80703B, Руководство по установке

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I R I R I R I R I RC U L C U L C U L C U L C U LA A A A AT I N G T I N G T I N G T I N G T I N G
A A
A A
A
I R I R I R I R I R A N D A N D A N D A N D A N D
F F
F F
F
I L I L I L I L I LT E R S T E R S T E R S T E R S T E R S
G G
G G G
AS AS
AS AS AS
P P
P P P
IPING IPING
IPING IPING IPING
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ONNECTIONS ONNECTIONS
ONNECTIONS ONNECTIONS ONNECTIONS
T
O AVOID POSSIBLE UNSATISFACTORY OPERATION OF EQUIPMENT
DAMAGE DUE TO UNDERFIRING OR EQUIPMENT
,
USE THE PROPER SIZE
OF NATURAL
/
PROPANE GAS PIPING NEEDED WHEN RUNNING PIPE FROM
THE METER
/
TANK TO THE FURNACE
.
WARNING
When sizing a trunk line, be sure to include all appliances which will
operate simultaneously.
The gas piping supplying the furnace must be properly sized based
on the gas flow required, specific gravity of the gas, and length of
the run. The gas line installation must comply with local codes, or in
their absence, with the latest edition of the National Fuel Gas Code,
NFPA 54/ANSI Z223.1.
Natural Gas Capacity of Pipe
In Cubic Feet of Gas Per Hour (CFH)
Length of Nominal Black Pipe Size
Pipe in Feet 1/2" 3/4" 1" 1 1/4" 1 1/2"
10 132 278 520 1050 1600
20 92 190 350 730 1100
30 73 152 285 590 980
40 63 130 245 500 760
50 56 115 215 440 670
60 50 105 195 400 610
70 46 96 180 370 560
80 43 90 170 350 530
90 40 84 160 320 490
100 38 79 150 305 460
(Pressure 0.5 psig or less and pressure drop of 0.3" W.C.; Based on
0.60 Specific Gravity Gas)
CFH =
BTUH Furnace Input
Heating Value of Gas (BTU/Cubic Foot)
To connect the furnace to the building’s gas piping, the installer
must supply a ground joint union, drip leg, manual shutoff valve,
and line and fittings to connect to gas valve. In some cases, the
installer may also need to supply a transition piece from 1/2" pipe to
a larger pipe size.
The following stipulations apply when connecting gas piping.
• Use black iron or steel pipe and fittings for the building
piping.
• Use pipe joint compound on male threads only. Pipe joint
compound must be resistant to the action of the fuel used.
• Use ground joint unions.
• Install a drip leg to trap dirt and moisture before it can
enter the gas valve. The drip leg must be a minimum of
three inches long.
• Install a 1/8" NPT pipe plug fitting, accessible for test gage
connection, immediately upstream of the gas supply
connection to the furnace.
• Use two pipe wrenches when making connection to the
gas valve to keep it from turning. The orientation of the
gas valve on the manifold must be maintained as shipped
from the factory.
• Install a manual shutoff valve between the gas meter and
unit within six feet of the unit. 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:
–
Rigid metallic pipe and fittings.
–
Semi-rigid metallic tubing and metallic fittings.
Aluminum alloy tubing must not be used in exterior
locations.
–
Use listed gas appliance connectors in accordance with
their instructions. Connectors must be fully in the same
room as the furnace.
–
Protect connectors and semi-rigid 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, or insulation, or subjected to repeated
wetting by liquids such as water (except rain water),
detergents, or sewage.
Drip Leg
Ground Joint Pipe Union
To Be Installed Ahead of
Gas Valve
Reducing Coupling
1/2” x 1/8” with 1/8”
Pipe Plug to Measure
Line Gas Pressure
Height Required
By Local Code
Location of Manual Valve
(Installed Ahead of
Ground Joint Pipe Union)
``
General Furnace Layout
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PFLOW PFLOW PFLOW PFLOW PFLOW
I I I
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NSTALLATIONS NSTALLATIONS NSTALLATIONS NSTALLATIONS NSTALLATIONS
When the gas piping enters through the right side of the furnace , the
installer must supply the following fittings (starting from the gas
valve):
• Close nipple.
• 90 degree elbows.
• Straight pipe to reach the exterior of the furnace .
A ground joint union, drip leg, and manual shutoff valve must also
be supplied by the installer. In some cases, the installer may also
need to supply a transition piece from 1/2" to another pipe size.
When the gas piping enters through the left side of the furnace, the
installer must supply the following fittings (starting from the gas
valve):
• 90 degree elbow.
• Straight pipe to reach the exterior of the furnace.