5188236-BIM-A-0316
56
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 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 or
position the switch to the “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” on page 57.
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 13",
nor the operating pressure drop below 5.0" for natural gas
units. If gas pressure is outside these limits, contact the
local gas utility for corrective action.
Figure 25: Typical Single Stage Gas Valves
Figure 26: Typical 2 Stage Gas Valves
Manifold Gas Pressure Adjustment
Adjustments to the high-fire and low-fire (2 stage) gas flow may
be made by turning the pressure regulator adjusting screws on
the automatic gas valve.
Adjust as follows:
1.
Remove the adjustment screw cap(s) on the regulator.
2.
To decrease the gas pressure, turn the adjusting screw
counterclockwise.
3.
To increase the gas pressure, turn the adjusting screw
clockwise.
4.
Replace adjustment screw caps.
NOTE:
The factory set high-fire manifold pressure for these
furnaces is 3.50 IWG. The actual manifold pressure
depends on the local fuel heating value.
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. 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.
Pilot Adj.
(Under Screw)
“ON” - “OFF” Control
“ON” - “OFF” Control
High Fire Adj.
(Under Screw)
Honeywell
VR8204M
Regulator Adj. “HI”
(Under Screw)
Regulator Adj. “LO”
(Under Screw)
“ON” - “OFF” Control
Pilot Adj.
(Under Screw)
Honeywell
VR820RQ
