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349215-JIM-B-1008
54
Johnson Controls Unitary Products
OPERATING INSTRUCTIONS
TO LIGHT PILOT AND MAIN BURNERS:
1. Turn “off” electric power to unit.
2. Turn room thermostat to lowest setting.
3. Turn gas valve knob or switch to “on” position.
4. Turn “on” electric power to unit.
5. Set room thermostat to desired temperature.
(If thermostat “set” temperature is above room tem-
perature, 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, or turn gas valve switch to “off” position.
POST-START CHECK LIST (GAS)
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” page 55.
3. Check the supply gas pressure. It must be within
the limits shown on rating nameplate. Supply pres-
sure should be checked with all gas appliances in
the building at full fire. At no time should the
standby gas line pressure exceed 13", nor the
operating pressure drop below 5.0" for natural gas
units. If gas pressure is outside these limits, con-
tact the local gas utility for corrective action.
This furnace is equipped with an intermittent
pilot and automatic re-ignition system. DO
NOT attempt to manually light the pilot.
FIRE OR EXPLOSION HAZARD
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. A
Fire or explosion may result causing property
damage, personal injury or loss of life.
Use a commercially available soap solution
made specifically for the detection of leaks.
FIGURE 25 - TYPICAL GAS VALVES