5742640-TIM-A-0419
54
Johnson Controls Ducted Systems
9.
Turn unit electrical power off.
Operating Instructions
1.
Turn unit electrical power on.
2.
Set the room thermostat setting to lower than the room
temperature.
3.
Compressor will energize after the built-in time delay (five
minutes).
Post Start Check List
1.
Verify proper system pressures.
2.
Measure the temperature drop across the evaporator coil.
3.
Measure the system Amperage draw across all legs of 3
phase power wires.
4.
Measure the condenser fan amp draw.
Shut Down
1.
Set the thermostat to highest temperature setting.
2.
Turn off the electrical power to the unit.
Start-up (Gas Heat)
Pre-start Check List
Complete the following checks before starting the unit.
1.
Check the type of gas being supplied. Be sure that it is the
same as listed on the unit nameplate.
2.
Make sure that the vent and combustion air hoods have
been properly installed.
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 55.
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 23: Typical Single Stage Gas Valves
Figure 24: Typical 2 Stage Gas Valves
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
