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operates with the correct sequence of operation (see page
25). The over-temperature limit control should function to
turn off the gas valve within approximately four minutes
(the exact time depending on the effi ciency of the close-
off in blocking the return air to the unit). The circulating
air and combustion blowers should continue to run when
the over-temperature limit control switch opens. Remove
the close-off immediately after the over-temperature limit
control opens. If the unit operates for more than four minutes
with no return air, set the thermostat to a temperature
below room temperature, shut off the power to the unit,
and replace the over-temperature limit control.
COMPONENT FUNCTIONS
Flame Sensor —
The fl ame sensor acts to prove that
fl ame has carried over from the ignitor to the right-most
burner. If no fl ame is sensed, the unit will be shut down
automatically.
Flame Roll-Out Control —
The fl ame roll-out control acts
to verify that the burner fl ame is being drawn into the heat
exchanger tubes. If the burner fl ame is not being drawn
into the heat exchanger tubes, the roll-out control will
open within several seconds and the integrated control
diagnostic light will fl ash one time. The circulating air
blower and combustion blower will continue to operate if
the fl ame roll-out control opens.
Gas Valve —
The gas valve acts to control the fl ow of
gas to the burners. When the gas valve is energized it
automatically opens and regulates the gas pressure in
the manifold.
Pressure Switch —
The pressure switch acts to verify
that the inducer motor is drawing the combustion gases
through the heat exchanger tubes and venting the gases
through the vent system.
Over-Temperature Limit Control —
The over-temperature
limit control acts to prevent the air temperature leaving the
unit from exceeding the maximum outlet air temperature.
If the limit opens, the integrated control diagnostic will
fl ash one time. The circulating air blower and combustion
blower will continue to operate if the over-temperature
limit control opens.
UNIT MAINTENANCE
WARNING:
To avoid risk of electrical shock, personal
injury, or death, disconnect all electrical power
to the unit before performing any maintenance
or service. The unit may have more than one
electrical supply.
CAUTION:
Use care when removing parts from this unit.
Personal injury can result from sharp metal
edges present in all equipment of sheet metal
construction.
Refrigerant Charging —
The packaged gas/electric units
are fully charged at the factory with R410A refrigerant. The
system refrigerant charge can be checked and adjusted
through the service ports provided behind the service
panel. Use only gauge lines which have a “Schrader”
depression device present to actuate the valve. Refrigerant
charging must be done by qualifi ed personnel familiar
with safe and environmentally responsible refrigerant
handling procedures.
WARNING:
The gas/electric units are shipped fully charged
and ready for installation. When a system is
installed according to these instructions, no
refrigerant charging is required. If repairs make it
necessary for evacuation and charging, it should
only be done by qualifi ed, trained personnel
thoroughly familiar with this equipment. Some
local codes require licensed installation/service
personnel to service this type of equipment. Under
no circumstances should the owner attempt to
install and/or service this equipment. Failure to
comply with this warning could result in property
damage, personal injury, or death.
Routine Maintenance —
Proper maintenance is important
to achieve optimum performance from the air conditioner.
The ability to properly perform maintenance on this
equipment requires certain mechanical skills and tools.
If you do not possess these skills, contact your dealer
for maintenance. Consult your local dealer about the
availability of maintenance contracts. At a minimum,
routine maintenance should include the following:
Air Filter —
Inspect and clean or replace the air fi lter
every three to four weeks.
WARNING:
Never operate the unit without a fi lter in place.
Dust and lint in the return air can build up
on internal components, resulting in loss of
effi ciency, equipment damage, and possible fi re
risk.
