Gas Piping Connections - Maytag Amana CVC96 Series Installation Instructions Manual

G P C
AS IPING ONNECTIONS
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.
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. Refer to Gas Piping Connections figure for
typical gas line connections 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 rack, 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.
T
O AVOID POSSIBLE UNSATISFACTORY OPERATION OF EQUIPMENT
DAMAGE DUE TO UNDERFIRING OR EQUIPMENT
/
OF NATURAL PROPANE GAS PIPING NEEDED WHEN RUNNING PIPE FROM
/
THE METER TANK TO THE FURNACE
Natural Gas Capacity of Pipe
In Cubic Feet of Gas Per Hour (CFH)
Length of
"
Pipe in Feet ½
10 132
20 92
30 73
40 63
50 56
60 50
70 46
80 43
90 40
100 38
(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)
29
WARNING
,
USE THE PROPER SIZE
.
Nominal Black Pipe Size
" "
¾ 1 1¼"
278 520 1050
190 350 730
152 285 590
130 245 500
115 215 440
105 195 400
96 180 370
90 170 350
84 160 320
79 150 305
_________
1 ½"
1600
1100
980
760
670
610
560
530
490
460