826081-XIM-C-0214
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Johnson Controls Unitary Products
2.
Turn room thermostat to lowest setting.
3.
Turn gas valve knob to “on” position.
4.
Turn “on” electric power to unit.
5.
Set room thermostat to desired temperature.
(If thermostat “set” temperature is above room
temperature, pilot burner ignition will occur and, after an
interval to prove pilot flame, main burners will ignite).
To Shut Down:
1.
Turn “off” electric power to unit.
2.
Depress knob of gas valve while turning to “off” position.
Post-Start Check List (Gas)
FIRE OR EXPLOSION HAZARD
After the entire control circuit has been energized and the
heating section is operating, make the following checks:
1.
Check for gas leaks in the unit piping as well as the supply
piping.
2.
Check for correct manifold gas pressures. See “Checking
Gas Input” on page page 37.
3.
Check the supply gas pressure. It must be within the limits
shown on rating nameplate. Supply pressure should be
checked with all gas appliances in the building at full fire. At
no time should the standby gas line pressure exceed 3.24
kPa (13.0"), nor the operating pressure drop below 1.25
kPa (5.0") for natural gas units. If gas pressure is outside
these limits, contact the local gas utility for corrective
action.
Manifold Gas Pressure Adjustment
1 / 8 " G A P B E T W E E N C A R R Y - O V E R
T U B E A N D F L A M E S E N S O R B U L B
C A R R Y - O V E R T U B E
F L A M E S E N S O R B U L B
B U R N E R A S S E M B L Y B R A C K E T
Small adjustments to the high-fire gas flow may be made by
turning the pressure regulator adjusting screw on the automatic
gas valve.
Adjust as follows:
1.
Remove the cap on the regulator. It's located next to the
push-on electrical terminals.
2.
To decrease the gas pressure, turn the adjusting screw
counterclockwise.
3.
To increase the gas pressure, turn the adjusting screw
clockwise.
NOTE:
The correct manifold pressure for these furnaces is 872
± 74 Pa gauge (3.50 IWG ±0.3).
Pilot Checkout
The pilot flame should envelope the end of the flame sensor. To
adjust pilot flame, (1) remove pilot adjustment cover screw, (2)
increase or decrease the clearance for air to the desired level,
(3) be sure to replace cover screw after adjustment to prevent
possible gas leakage.
Put the system into operation and observe through complete
cycle to be sure all controls function properly.
Burner Instructions
To check or change burners, pilot or orifices, CLOSE MAIN
MANUAL SHUT-OFF VALVE AND SHUT OFF ALL ELECTRIC
POWER TO THE UNIT.
Failure to follow the safety warning exactly could result
in serious injury, death or property damage.
Never test for gas leaks with an open flame. use a
commercially available soap solution made specifically
for the detection of leaks to check all connections. A fire
or explosion may result causing property damage,
personal injury or loss of life.
Figure 20: Typical Gas Valves
Figure 21: Proper Flame Adjustment
