Operating instructions

13
With Power And Gas On:
Put unit into heating cycle and turn on all other gas consuming
appliances.
Natural Min. 5.0" W.C., Max. 10.0" W.C.
Propane Min. 11.0" W.C., Max. 13.0" W.C.
Inlet Gas Pressure
NOTE: Inlet Gas Pressure Must Not Exceed the Maximum Value
Shown.
If operating pressures differ from above, make necessary
pressure regulator adjustments, check piping size, etc., and/or
consult with local utility.
Manifold Pressure Check
A ”U” Tube manometer having a scale range from 0 to 12 inches
of water should be used for this measurement. The manifold
pressure must be measured with the burners operating.
Honeywell Model VR8205, White-Rodgers Models 36E22/
36F22:
A tapped opening is provided in the gas valve to facilitate
measurement of the manifold pressure.
White Rodgers Model 36G22:
Using a 3/32 inch hex wrench, loosen the outlet pressure tap
screw 1 turn only (DO NOT REMOVE). Attach a length of 5/16
inch hose to the outlet pressure tap boss. Connect the 5/16
inch hose to a water manometer or other adequate gauge.
To adjust the pressure regulator, remove the adjustment screw
or cover on the gas valve. Turn out (counterclockwise) to
decrease pressure, turn in (clockwise) to increase pressure.
Only small variations in gas flow should be made by means of
the pressure regulator adjustment. In no case should the final
manifold pressure vary more than plus or minus 0.3 inches water
column from the specified nominal pressure. Any major changes
in flow should be made by changing the size of the burner
orifices. The measured input rate to the furnace must not exceed
the rating specified on the unit rating plate.
For natural gas, the manifold pressure must be between 3.2
and 3.8 inches water column (3.5 nominal).
For propane gas, the manifold pressure must be between 9.7
and 10.3 inches water column (10.0 nominal).
Gas Input (Natural Gas Only) Check
NOTE: On outdoor equipment, the gas input will vary with the
temperature of the gas. Rated input will be obtained at
approximately 10° F. With warmer ambient and gas
temperatures, the input will decrease. Example: At 70° F the
input will decrease 12%.
To measure the gas input using the gas meter proceed as
follows:
1. Turn off gas supply to all other appliances except the unit.
2. With the unit operating, time the smallest dial on the meter
for one complete revolution. If this is a 2 cubic foot dial,
divide the seconds by 2; if it is a 1 cubic foot dial, use the
seconds as is. This gives the seconds per cubic foot of gas
being delivered to the unit.
3. INPUT=GAS HTG VALUE x 3600 / SEC. PER CUBIC FOOT
Example: Natural gas with a heating value of 1000 BTU per
cubic foot and 34 seconds per cubic foot as determined by
Step 2, then:
Input = 1000 x 3600 / 34 = 106,000 BTU per Hour. NOTE:
BTU content of the gas should be obtained from the gas
supplier. This measured input must not be greater than
shown on the unit rating plate.
4. Relight all other appliances turned off in step 1. Be sure all
pilot burners are operating.
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; all 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
temperature 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.
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 selected HEAT
FAN OFF delay.
Blower Speed Adjustment
WARNING
T
O 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 on the unit to verify speed tap
settings.
Blower speeds can be adjusted on the ignition control board.
Both heat speed and cool speed terminals are supplied on
the board along with two unused motor lead terminals.