12
Proper Piping Practice
NOTE: The unit gas supply entrance is factory sealed with plugs.
Keep plugs in place until gas supply is ready to be installed. Once
ready, replace the plugs with the supplied grommets and install
gas supply line.
Check Gas Piping
IMPORTANT:
■
The unit and its gas connections must be leak tested before
placing in operation.
■
Do not use a match or open flame to test for leaks.
■
Do not exceed specified pressures for testing.
■
Disconnect this unit and its shutoff valve from the gas supply
during any pressure testing of the system at test pressures in
excess of
¹⁄₂
psig (3.48 kPa).
■
Close the manual shutoff valve during any pressure testing of
the gas supply piping system at test pressures equal to or
less than
¹⁄₂
psig (3.48 kPa).
There will be air in the gas supply line after testing for leaks on a
new installation. Therefore, the air must be bled from the line by
loosening the ground joint union until pure gas is expelled.
Tighten the ground joint union and wait for 5 minutes until all gas
has been dissipated in the air. Be certain there is no open flame in
the vicinity during air bleeding procedure. The unit is placed in
operation by closing the main electrical disconnect switch for the
unit.
Install Propane Gas
NOTE: Propane gas conversion kits must be installed to convert
units to propane gas.
A gas detecting warning system is the only reliable way to detect
a propane gas leak. Rust can reduce the level of odorant in
propane gas. Do not rely on your sense of smell. Contact a local
propane gas supplier about installing a gas detecting warning
system.
All propane gas equipment must conform to the safety standards
of the National Board of Fire Underwriters, NBFU Manual 58.
For satisfactory operation, propane gas supply pressure must be
within 9.7" W.C. to 10.3" W.C. at the furnace manifold with all gas
appliances in operation.
Maintaining proper gas pressure depends on 3 main factors:
■
Vaporization rate, depending on the temperature of the liquid
and the wetted surface area of the container or containers.
■
Proper pressure regulation. Two-stage regulation is
recommended for both cost and efficiency.
■
Pressure drop in the lines between the regulators, and
between 2
nd
stage regulator and the appliance. Pipe size
required will depend on the length of the pipe run and the
total load of all appliances.
A. Manual shutoff valve
B. Drip leg
C. Ground joint union (installed upstream of
gas control valve)
D. Grommet
D
C
B
A
Goodman 90
To prevent property damage or personal injury due to fire,
the following instructions must be performed regarding
gas connections and pressure testing:
-The unit and its gas connections must be leak tested
before placing in operation. Because of the danger of
explosion or fire, never use a match or open flame to test
for leaks. Never exceed specified pressures for testing.
Higher pressure may damage gas control valve and cause
overfiring which may result in premature heat exchange
failure.
-The unit and its gas shutoff valve must be disconnected
from the gas supply during any pressure testing of that
system at test pressures in excess of
¹⁄₂
psig (3.48 kPa).
-This unit must be isolated from the gas supply system
by closing its manual shutoff valve during any pressure
testing of the gas supply piping system at test pressures
equal to or less than
¹⁄₂
psig (3.48 kPa).
CAUTION
Goodman 91
To avoid property damage or personal injury, be sure
there is NO OPEN FLAME in the vicinity during air
bleeding.
WARNING
Goodman 92
To avoid property damage, personal injury or death due
to fire or explosion caused by a propane gas leak, install
a gas detecting warning device. Since rust can reduce the
level of odorant in propane gas, a gas detecting warning
device is the only reliable way to detect a propane gas
leak. Contact a local propane gas supplier about installing
a gas detecting warning device.
WARNING
