5835254-YIM-A-1119
46
Johnson Controls Ducted Systems
Flash codes
The ICB initiates a flash code associated with errors within the
system, Table 31 on page 56.
Resets
Resets remove the call for heating by lowering the thermostat
setting lower than the conditioned space temperature. This
resets any flash codes.
Gas heat anticipator setpoints
The anticipator setpoint must be correct. Too high of a setting
results in longer heat cycles and a greater temperature swing in
the conditioned space. Reducing the value below the correct
setpoint gives shorter ON cycles and may result in the lowering
of the temperature within the conditioned space. See Table 27
for the required gas heat anticipator setting.
Cooling start-up
Pre-start checklist
When the installation is complete, perform the following checks:
1.
Check the electrical supply voltage being supplied. Verify
that it is the same as the voltage listed on the unit
nameplate.
2.
Set the room thermostat to the off position.
3.
Turn on electrical power to the unit.
4.
Set the room thermostat fan switch to on.
5.
Check the indoor blower rotation.
• If the blower rotation is in the wrong direction, see
Check the blower drive belt tension.
6.
Check the unit supply air (CFM).
7.
Measure the evaporator fan motor's amp draw.
8.
Set the room thermostat fan switch to off.
9.
Turn off electrical power to the unit.
Operating the unit
1.
Turn on electrical power to the unit.
Note:
Before each cooling season, you must energize the
crankcase heaters at least 10 hours before the system
is put into operation.
2.
Set the room thermostat setting lower than the room
temperature.
First stage compressors energize after the built-in time
delay of five minutes.
The second stage of the thermostat energizes the second
stage compressor if needed.
Post-start checklist
1.
Verify proper system pressures for both circuits.
2.
Measure the temperature drop across the evaporator coil.
Gas heat start-up
Pre-start checklist
When the installation is complete, perform the following checks.
1.
Check the type of gas supply. Verify that it is the same as
the gas supply listed on the unit nameplate.
2.
Verify that the vent outlet and combustion air inlet are free
of any debris or obstruction.
Operating instructions
Lighting the main burners
1.
Turn off electrical power to unit.
2.
Set the room thermostat to lowest setting.
3.
Turn the gas valve counter-clockwise to the ON position
(see Figure 30).
4.
Turn on electrical power to unit.
If the set temperature on the thermostat is above room
temperature, the main burners ignite. If a second stage of
heat is called for, the main burners for second stage heat
ignite for the second stage heat.
Post start checklist
After the entire control circuit has been energized and the
heating section is operating, perform the following checks:
1.
Check for gas leaks in the unit piping and the supply
piping.
Table 27: Gas heat anticipator setpoints
Setting, amps
W1
W2
0.65
0.1
This furnace is equipped with an automatic re-ignition
system. Do not attempt to manually light the pilot.
This furnace is equipped with an automatic re-ignition
system. Do not attempt to manually light the pilot.
