Amana GUCA045AX30 Service Instructions Manual page 41

A different pressure switch may be required at high altitude
3
regardless of the BTU/ft
S-19 HIGH ALTITUDE APPLICATION (USA) section lo-
cated in the SERVICING section of this manual or an Amana
distributor for a tabular listing of appropriate altitude ranges
and corresponding manufacturer's pressure switch kits.
Propane Gas Conversion
WARNING
Possible death, personal injury or property damage may
occur if the correct conversion kits are not installed.
The appropriate kits must be applied to insure safe and
proper furnace operation. All conversions must be per-
formed by a qualified installer or service agency.
This unit is configured for natural gas. The appropriate
manufacturer's propane gas conversion kit, must be ap-
plied for propane gas installations. Refer to the "Propane
Gas and/or High Altitude Installations" section for details.
Gas Valve
This unit is equipped with a 24 volt gas valve controlled
during furnace operation by the integrated control module.
As shipped, the valve is configured for natural gas. The
valve is field convertible for use with propane gas by re-
placing the regulator spring with a propane gas spring from
an appropriate manufacturer's propane gas conversion kit.
Taps for measuring the gas supply pressure and manifold
pressure are provided on the valve.
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 lo-
cated on the furnace or on page 6, and the "Furnace Startup"
and "Furnace Shutdown" sections for use of this control
during start up and shut down periods.
Gas Piping Connections
General
CAUTION
To avoid possible unsatisfactory operation or equip-
ment 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.
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.
PRODUCT DESIGN
content of the fuel used. Refer to
Natural Gas Capacity of Pipe
In Cubic Feet of Gas Per Hour (CFH)
Length of
Pipe in Feet 1/2"
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)
BTUH Furnace Input
CFH =
Heating Value of Gas (BTU/Cubic Foot)
To connect the furnace to the building's gas piping, the in-
staller 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 tran-
sition piece from 1/2" pipe to a larger pipe size.
The following stipulations apply when connecting gas pip-
ing. Refer to the figures on page 40 for typical gas line con-
nections to the furnace.
• Use black iron or steel pipe and fittings for the build-
ing 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 mini-
mum 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 in-
stalled, the union must be downstream of the manual
shutoff valve, between the shutoff valve and the fur-
nace.
• Tighten all joints securely.
• Connect the furnace to the building piping by one of
the following methods:
– Rigid metallic pipe and fittings.
– Semirigid metallic tubing and metallic fittings.
Aluminum alloy tubing must not be used in exterior
locations. In order to seal the grommet cabinet pen
etration, rigid pipe must be used to reach the out-
side of the cabinet. A semirigid connector to the
gas piping may be used from there.
Nominal Black Pipe Size
3/4" 1" 1 1/4"
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
41
1 1/2"
1600
1100
980
760
670
610
560
530
490
460
Rev. 0