Page 22
GROUND
JOINT
UNION
AUTOMATIC
GAS VALVE
(with manual
shut−off valve)
FIELD
PROVIDED
AND INSTALLED
GROUND
JOINT
UNION
Left Side Piping
(Standard)
Right Side Piping
(Alternate)
AUTOMATIC
GAS VALVE
(with manual
shut−off valve)
DRIP LEG
DRIP LEG
MANUAL
MAIN SHUT−OFF
VALVE
(With 1/8 in. NPT
Plugged Tap Shown)
MANUAL
MAIN SHUT−OFF
VALVE
(With 1/8 in. NPT
Plugged Tap
Shown)
FIGURE 19
Leak Check
After gas piping is completed, carefully check all piping
connections (factory− and field−installed) for gas leaks. Use
a leak detecting solution or other preferred means.
NOTE − If emergency shutoff is necessary, shut off the
main manual gas valve and disconnect the main power to
the furnace. The installer should properly label these de-
vices.
CAUTION
Some soaps used for leak detection are corrosive to
certain metals. Carefully rinse piping thoroughly af-
ter leak test has been completed. Do not use
matches, candles, flame or other sources of ignition
to check for gas leaks.
The furnace must be isolated from the gas supply system
by closing its individual manual shut-off valve during any
pressure testing of the gas supply system at pressures
less
than or equal to
1/2 psig (3.48 kPa, 14 inches w.c.).
IMPORTANT
When testing pressure of gas lines, gas valve must
be disconnected and isolated. See figure 20. Gas
valves can be damaged if subjected to pressures
greater than 1/2 psig (3.48 kPa, 14 inches w.c.).
MANUAL MAIN
SHUT−OFF VALVE
WILL NOT HOLD
NORMAL TEST
PRESSURE
CAP
ISOLATE
GAS VALVE
FURNACE
FIGURE 20
Electrical
ELECTROSTATIC DISCHARGE (ESD)
Precautions and Procedures
CAUTION
Electrostatic discharge can affect electronic compo-
nents. Take precautions during furnace installation
and service to protect the furnace’s electronic con-
trols. Precautions will help to avoid control exposure
to electrostatic discharge by putting the furnace, the
control and the technician at the same electrostatic
potential. Neutralize electrostatic charge by touch-
ing hand and all tools on an unpainted unit surface,
such as the gas valve or blower deck, before per-
forming any service procedure.
The unit is equipped with a field make−up box. The make−
up box may be moved to the right side of the furnace to fa-
cilitate installation. If the make−up box is moved to the right
side, the excess wire must be pulled into the blower
compartment. Secure the excess wire to the existing harn-
ess to protect it from damage.
INTERIOR MAKE−UP BOX INSTALLATION
MAKE−UP
BOX
Right Side
FIGURE 21
