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2
TO SHUT UNIT OFF
See Fig. 1 for location of gas valve. Refer to Fig. 3 while
proceeding with the following steps.
Step 1 —
Set room thermostat to lowest temperature setting
and set SYSTEM switch to OFF position.
Step 2 —
Close the external manual gas valve.
Step 3 —
Turn off the electrical power supply to the unit
and install lockout tag.
Step 4 —
Remove the heat section access panel.
Step 5 —
Turn the control dial on the internal gas valve
counterclockwise
to the OFF position.
Step 6 —
Replace the heat section access panel.
Step 7 —
If unit is being shut down because of a malfunc-
tion, call your dealer as soon as possible.
If unit is being shut down because the heating season has
ended, restore electrical power to the unit to ensure operation
of the cooling system during the cooling season.
Should overheating occur, or the gas supply fail to shut off,
shut off the manual gas valve to the unit before shutting off the
electrical supply.
Do not use this unit if any part has been under water. Imme-
diately call a qualified service technician to inspect the unit and
to replace any part of the control system and any gas control
which has been under water.
MAINTAINING YOUR UNIT
All maintenance should be handled by skilled, experienced
personnel. Your dealer can help you establish a standard
procedure.
For your safety, keep the area around the unit clear and free
of combustible materials, gasoline and other flammable liquids
and vapors.
To assure proper functioning of the unit, flow of combustion
and ventilating air must not be obstructed from reaching the
unit. Clearance of at least 6 ft on all sides is required.
ROUTINE MAINTENANCE AND CARE
FOR THE EQUIPMENT OWNER
Before proceeding with those things you might want to
maintain yourself, please carefully consider the following:
Air Filter(s) —
Air filters should be checked at least
every 3 or 4 weeks and changed or cleaned whenever they
become dirty. Table 1 indicates the correct filter size for your
unit. Open the filter access panel to replace or inspect the
filters. All units have filter tracks into which the filters slide.
Remove the filters by pulling the filter slide outward from the
track. See Fig. 4 for filter access panel location. Note the direc-
tion of flow arrows on the filter frame.
If you have difficulty in locating your air filter in the return-
air duct system, or if you have questions concerning proper fil-
ter maintenance, contact your dealer for instructions. When re-
placing your unit filters, always use the same size and type of
filter that was originally supplied by the installer.
Units with outdoor air capability have cleanable filters for
the outdoor air. These filters should be checked annually and
cleaned as necessary. Remove by pulling out the middle of the
hood top. Push up on the center filter and then remove. Slide
the other filters to the center and repeat.
.
Table 1 — Indoor Air Filter Data*
*When replacing filters, always use the same type and size originally
supplied.
If the main burners fail to light, or the blower fails to come
on, shut down gas heating section and call your dealer for
service. Failure to follow these requirements could result in
serious personal injury.
Do not turn off the electrical power to unit without first
turning off the gas supply.
Failure to follow these procedures can result in serious
fire or personal injury.
1. TURN OFF GAS SUPPLY AND ELECTRICAL
POWER TO YOUR UNIT BEFORE SERVICING
OR PERFORMING MAINTENANCE.
2. Do not turn off electrical power to this unit without
first turning off the gas supply.
3. When removing access doors or performing mainte-
nance functions inside your unit, be aware of sharp
sheet metal parts and screws. Although special care
has been taken to reduce sharp edges to a minimum,
be extremely careful when handling parts or reaching
into the unit.
Never operate your unit without filters in place. Failure to
heed this warning may result in damage to the blower
motor and/or compressor. An accumulation of dust and lint
on internal parts of your unit can cause loss of efficiency
and in some cases, fire.
UNIT
48HG
TYPE OF FILTER
QUANTITY...SIZE
(in.)
014-
024
Standard Throwaway, Optional 30%,
or Accessory 65% Pleated
9...16 x 25 x 2
028
Standard Throwaway, Optional 30%,
or Accessory 65% Pleated
9...18 x 24 x 2
HEAT
EXCHANGER
SECTION
IGC BOARD
(HIDDEN)
COMBUSTION
FAN HOUSING
MAIN BURNER
SECTION
INDUCED
DRAFT
MOTOR
MAIN GAS
VALVE
LEGEND
Fig. 1 — Typical Gas Heating Section
IGC —
Integrated Gas Controller