20 18-CD34D1-5-EN
INSTALLER’S GUIDE
LIGHTING INSTRUCTIONS
Lighting instructions appear on each unit. Each installation
must be checked out at the time of initial start up to insure
proper operation of all components. Check out should include
putting the unit through one complete cycle as outlined below.
Turn on the main electrical supply and set the thermostat above
the indicated temperature. The ignitor will automatically heat,
then the gas valve is energized to permit the flow of gas to the
burners. After ignition and flame is established, the flame control
module monitors the flame and supplies power to the gas valve
until the thermostat is satisfied.
To shut off
For complete shutdown: Move the control switch on the main
gas valve to the “OFF” position (See Figures 18). Disconnect the
electrical supply to the unit.
▲
CAUTION
!
If this is done during the cold weather months,
provisions must be taken to prevent freeze-up of
all water pipes and water receptacles.
Whenever your house is to be vacant, arrange to have someone
inspect your house for proper temperature. This is very
important in below freezing weather. If for any reason your
furnace should fail to operate damage could result, such as
frozen water pipes.
CONTROL AND SAFETY SWITCH
ADJUSTMENT
LIMIT SWITCH CHECK OUT
The limit switch is a safety device designed to close the gas valve
should the furnace become overheated. Since proper operation
of this switch is important to the safety of the unit, it must be
checked out on initial start up by the installer.
To check for proper operation of the limit switches, set the
thermostat to a temperature higher than the indicated temperature
to bring on the gas valve. Restrict the airflow by blocking the
return air or by disconnecting the blower. When the furnace
reaches the maximum outlet temperature as shown on the rating
plate, the burners must shut off. If they do not shut off after a
reasonable time and overheating is evident, a faulty limit switch
is probable and the limit switch must be replaced. After checking
the operation of the limit control, be sure to remove the paper or
cardboard from the return air inlet, or reconnect the blower.
AIRFLOW ADJUSTMENT
Check inlet and outlet air temperatures to make sure they are
within the ranges specified on the furnace rating nameplate. If
the airflow needs to be increased or decreased, see the wiring
diagram for information on changing the speed of the blower
motor.
▲
WARNING
!
Disconnect power to the unit before removing the
blower door. Failure to follow this warning could
result in property damage, personal injury or
death.
This unit is equipped with a blower door switch which cuts power
to the blower and gas valve causing shutdown when the door is
removed. Operation with the door removed or ajar can permit the
escape of dangerous fumes. All panels must be securely closed at
all times for safe operation of the furnace.
NOTE: Direct drive motors have bearings which are
permanently lubricated and under normal use, lubrication is
not recommended
INDOOR BLOWER TIMING
The control module controls the indoor blower. The blower starts
approximately 45 seconds after ignition. The FAN-OFF period
is approximately 100 seconds from the interruption of gas flow.
ROOM AIR THERMOSTAT HEAT
ANTICIPATOR ADJUSTMENT
Set the thermostat heat anticipator according to the current flow
measured, or the settings found in the notes on the furnace wiring
diagram (found inside the furnace casing).
INSTRUCTIONS TO THE OWNERS
In the event that electrical, fuel, or mechanical failures occur,
the owner should immediately turn the gas supply off at the
manual gas valve, located in the burner compartment (See
Figure 17). Also turn off electrical power to the furnace and
contact the service agency designated by your dealer.
▲
WARNING
!
Should overheating occur, or the gas supply fail
to shut off, shut off the gas valve to the unit before
shutting off the electrical supply. Failure to follow
this warning could result in property damage,
personal injury, or death.
OPERATING INFORMATION
FLAME ROLL-OUT DEVICE
All models are equipped with a thermal control device on the
burner cover. In case of flame roll-out, the device will cause the
circuit to open which shuts off all flow of gas.
Abnormal Conditions
1.
EXCESSIVE COMBUSTION VENT PRESSURE OR
FLUE BLOCKAGE
If pressure against the induced draft blower outlet becomes
excessive, the pressure switch will shut off the gas valve
until acceptable combustion pressure is again available.
2.
LOSS OF FLAME OR GAS SUPPLY FAILURE
If loss of flame occurs during a heating cycle (when flame is
not present at the sensor), the control module will retry the
