Goodman Mfg MVM96 사용자 설명서

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G
AS
 V
ALVE
This unit is equipped with a 24 volt gas valve which modulates by
pneumatic linkage to the combustion air blower Taps for mea-
suring the gas supply pressure and manifold pressure are provided
on the valve. This is a non-convertible gas valve equipped for
natural gas.
The gas valve has a manual ON/OFF control located on the valve
itself.  This control may be set only to the “ON” or “OFF” position.
Refer to the lighting instructions label or  Startup Procedure &
Adjustment 
for use of this control during start up and shut down
periods.
G
AS
 P
IPING
 C
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 when sizing a trunk line.
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.  Re-
fer to Gas Piping Connections figure for typical gas line connec-
tions to the furnace.
Gas piping must be supported external to the furnace
cabinet so that the weight of the gas line does not distort
the burner rakc, manifold or gas valve.
Use black iron or steel pipe and fittings for building piping.
Where possible, use new pipe that is properly chamfered,
reamed, and free of burrs and chips.  If old pipe is used, be
sure it is clean and free of rust, scale, burrs, chips, and old
pipe joint compound.
Use pipe joint compound on male threads ONLY.  Always
use pipe joint compound (pipe dope) that is APPROVED
FOR ALL GASSES.  DO NOT apply compound to the first
two threads.
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.
Always use a back-up wrench when making the 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.  Maximum torque for the gas valve
connection is 375 in-lbs; excessive over-tightening may
damage the gas valve.
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.  In order to seal the grommet cabinet
penetration, rigid pipe must be used to reach the outside
of the cabinet.  A semi-rigid connector to the gas piping
may be used from there.
Use listed gas appliance connectors in accordance with
their instructions.  Connectors must be fully in the same
room as the furnace.
Protect 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,
or insulation, or subjected to repeated wetting by liquids
such as water (except rain water), detergents, or sewage.