Goodman Amana AMH8 Service Instructions Manual page 31

PRODUCT DESIGN
This unit is configured for natural gas. The appropriate
manufacturer's propane gas conversion kit, must be ap-
plied for propane gas installations.
• Two-stage furnace models using a White-Rodgers
36G54 two-stage valve require an LPM-05 or LPM-
06 LP conversion kit.
• Two-stage furnace models using a Honeywell
VR9205 two-stage valve require an LPM-06 LP con-
version kit.
Refer to the specification sheet for the model you are
servicing. Refer to the "propane gas and/or High Alti-
tude Installations" section for details.
GAS VALVE
This unit is equipped with a 24 volt gas valve controlled
during furnace operation by the integrated control mod-
ule. As shipped, the valve is configured for natural gas.
The valve is field convertible for use with propane gas
by using the appropriate propane gas conversion kit.
Taps for measuring the gas supply pressure and mani-
fold pressure are provided on the valve.
NOTE: The gas supply pressure on White-Rodger "G"
model gas valve, used on single stage furnaces, can
be checked with a gas pressure test kit (Part
#0151K00000S) available through our authorized dis-
tributors.
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 Instruc-
tions Label or the "Putting the Furnace Into Operation"
section of this manual or the installation instructions
for use of this control during start up and shut down
periods.
GAS PIPING CONNECTIONS
T
O AVOID POSSIBLE UNSATISFACTORY OPERATION OR EQUIPMENT DAMAGE
DUE TO UNDERFIRING OF EQUIPMENT, USE THE PROPER SIZE OF
NATURAL/PROPANE GAS PIPING NEEDED WHEN RUNNING PIPE FROM THE
METER/TANK TO THE FURNACE.
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.
CAUTION
Natural Gas Capacity of Pipe In Cubic Feet of Gas Per Hour (CFH)
Length
Nominal Black P ip e S iz e
of
P ip e
1/2" 3/4"
In Feet
1 0 1 32 278
20 92 1 90
30 73 1 52
40 63 1 30
50 56 11 5
60 50 1 05
70 46 96
80 43 90
90 40 84
100 38 79
(Pressu re 0.5 p sig or less an d p ressu re d rop of 0.3W .C.; B ased on
0.60 S p ecif ic 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. Refer to the following figures for typical gas line
connections to the furnace.
1. Use black iron or steel pipe and fittings for the
building piping.
2. Use pipe joint compound on male threads only.
Pipe joint compound must be resistant to the ac-
tion of the fuel used.
3. Use ground joint unions.
4. 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.
5. Install a 1/8" NPT pipe plug fitting, accessible for
test gage connection, immediately upstream of
the gas supply connection to the furnace.
6. Use two pipe wrenches when making connection to
the gas valve to keep it from turning. The orienta-
tion of the gas valve on the manifold must be
maintained as shipped from the factory.
7. 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.
8. Tighten all joints securely.
1" 1- 1/4" 1- 1/2"
520 1 ,050 1 ,600
350 730 1 ,1 00
285 590 980
245 500 760
21 5 440 670
1 95 400 61 0
1 80 370 560
1 70 350 530
1 60 320 490
1 50 305 460
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