Main Burner Flame Check
Flames should be stable, soft and blue (dust may cause orange
tips but they must not be yellow) and extending directly outward
from the burner without curling, floating or lifting off.
Temperature Rise Check
Check the temperature rise through the unit by placing
thermometers in supply and return air registers as close to the
unit as possible. Thermometers must not be able to sample
temperature directly from the unit heat exchangers, or false
readings could be obtained.
1. All registers must be open; ail duct dampers must be in their
final (fully or partially open) position and the unit operated
for 15 minutes before taking readings.
2. The temperature rise must be within the range specified on
the rating plate.
NOTE: Air temperature rise is the temperature difference between
supply and return air.
With a properly designed system, the proper amount of
temperature rise will normally be obtained when the unit is
operated at rated input with the recommended blower speed,
if the correct amount of temperature rise is not obtained, it
may be necessary to change the blower speed. A higher blower
speed will lower the temperature rise. A slower blower speed
will increase the temperature rise.
NOTE: Blower speed MUST be set to give the correct air tempera-
ture rise through the unit as marked on the rating plate.
External Static Pressure Check
The total external static pressure must be checked on this unit
to determine if the airflow is proper.
Blower Speed Adjustments
TO AVOID PERSONAL INJURY OR DEATH DUE TO ELECTRIC SHOCK, REMOVE
ELECTRICAL POWER FROM THE UNIT BEFORE CHANGING SPEED TAPS ON THE
BLOWER MOTOR.
Refer to the wiring diagram in the appendix to verify speed tap
settings.
Blower speeds are to be changed at the ignition control board.
Both heat speed and cool speed terminals are supplied on the
board along with two unused motor lead terminals.
Limit Check
Check limit control operation after 15 minutes of operation by
blocking the return air grille(s).
1. After several minutes the main burners must go OFF. Blower
will continue to run.
2. Remove air restrictions and main burners will relight after a
cool down period of a few minutes.
Adjust the thermostat setting below room temperature.
1. Main burners must go OFF.
2. Circulating Air Blower will continue to run for 120, 135 or
150 seconds, depending on the setting.
Control Board (Top)
NOTE: If necessary, adjust fan OFF delay settings to obtain satis-
factory comfort level.
THIS UNIT MUST NOT BE USED AS A -CONSTRUCTION HEATER- DURING THE
FINISHING PHASES OF CONSTRUCTION ON A NEW STRUCTURE. THIS TYPE OF
USE MAY RESULT IN PREMATURE FAILURE OF THE UNIT DUE TO EXTREMELY
LOW RETURN AIR TEMPERATURES AND EXPOSURE TO CORROSIVE OR VERY
DIRTY ATMOSPHERES.
Unit Shutdown
1. Set the thermostat to lowest setting.
2. Turn off the electrical power supply to the unit.
3. Remove the heat exchanger door on the side of the unit by
removing screws.
4. Move (Figures 12 & 13) or rotate (Figure 14) the gas control
valve switch to the OFF position. Do not force.
5. Close manual gas shutoff valve external to the unit.
6. Replace the heat exchanger door on the unit.
7. If cooling and/or air circulation will be desired, turn ON the
electrical power.
COOLING STARTUP
NOTE: Check all manual reset limit controls in heating circuit if cool-
ing mode does not operate.
Compressor Protection Devices
The compressor includes components which are designed to
protect the compressor against abnormal operating conditions.
TO PREVENT PERSONAL INJURY OR DEATH, ALWAYS DISCONNECT ELECTRICAL,
POWER BEFORE INSPECTING OR SERVICING THE UNIT. A L L COMPRESSOR
PROTECTION DEVICES RESET AUTOMATICALLY, ENERGIZING THE CONTACTOR
AND OUTDOOR FAN.
Cooling Refrigerant Charging
Check unit charge before putting the cooling section into full
operation. The unit is factory charged with R-22 for nominal air
flow and static pressure conditions. The unit has a piston
flowrator expansion device. To ensure the unit is properly
charged for the intended application, check the unit refrigerant
superheat at the compressor. The refrigerant superheat is a
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