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Step 10 —
Set the temperature selector on room thermo-
stat slightly above room temperature to start unit. The induced-
draft combustion-air fan will start. Main gas valve will open
and main burners should ignite within 5 seconds. If the burner
does not light within 5 seconds, the ignition module will go
into a Retry mode after a period of approximately 22 sec-
onds (following the 5-second ignition period).
If the burners do not light within 15 minutes of the initial
call for heat, there is a lockout.
Step 11 —
Set the temperature selector on room ther-
mostat to desired setting.
1. If the main burners fail to light, or the blower fails
to start, shut down gas heating section and call your
dealer for service.
2. Never attempt to manually light the main burners on
unit with a match, lighter, or any other flame. If the
electric sparking device fails to light the main burn-
ers, refer to the following shutdown procedures, then
call your dealer as soon as possible.
Failure to follow these requirements could result in serious
personal injury.
TO SHUT UNIT OFF
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.
NOTE: If unit is being shut down because the heating sea-
son has ended, make sure to turn on power to cooling
system.
If unit is being shut down because of a malfunction, call
your dealer as soon as possible.
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. Im-
mediately 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.
Refer to Fig. 5 while proceeding with the following steps.
Step 1 —
Set the temperature selector on room thermo-
stat to lowest temperature setting and set SYSTEM switch
to OFF.
Step 2 —
Close the external manual shutoff valve.
Step 3 —
Turn off the electrical power supply to the unit.
Step 4 —
Remove the burner access panel.
Step 5 —
Turn the control dial on the internal gas valve
counterclockwise
to the OFF position.
Step 6 —
Replace the burner access panel.
Step 7 —
Restore electrical power to the unit and set SYS-
TEM switch to COOL to ensure operation of the cooling sys-
tem during the cooling season.
ROUTINE MAINTENANCE
All routine maintenance should be handled by skilled, ex-
perienced personnel. Your dealer can help you establish a
standard procedure.
For your safety, keep the unit area clear and free of com-
bustible materials, gasoline, and other flammable liquids and
vapors.
To assure proper functioning of the unit, flow of combus-
tion and ventilating air must not be obstructed from reaching
the unit. Clearance of at least 30 in. is required on all sides
except the duct side.
MAINTENANCE AND CARE FOR THE
EQUIPMENT OWNER
Before proceeding with those things you might want to
maintain yourself, please carefully consider the following:
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 panels or performing main-
tenance functions inside your unit, be aware of sharp
sheet metal parts and screws. Although special care
is taken to reduce sharp edges to a minimum, be ex-
tremely careful when handling parts or reaching into
the unit.
Air Filters —
Air filter(s) should be checked at least ev-
ery 3 or 4 weeks and changed or cleaned whenever it be-
comes dirty. Dirty filters produce excessive stress on the blower
motor and can cause the motor to overheat and shut down.
Table 1 indicates the correct filter size for your unit. Refer
to Fig. 6 to access the filter(s).
To replace or inspect filter(s) (or accessory filter rack when
supplied):
1. Remove the filter access panel using a
5
⁄
16
-in. nut driver.
2. Remove the filter(s) by pulling the filter(s) out of the unit.
If the filter(s) is dirty, clean or replace with new one.
When installing the new filter(s), note the direction of the
airflow arrows on the filter frame.
If you have difficulty in locating your air filter(s), or if
you have questions concerning proper filter maintenance, con-
tact your dealer for instructions. When replacing filters, al-
ways use the same size and type of filter that was supplied
originally by the installer.
BURNER
ACCESS PANEL
Fig. 2 — Dual Fuel Heat Pump
4