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SCHEDULED MAINTENANCE
The owner should be made aware of the fact, that, as with
any mechanical equipment the package unit requires regu-
larly scheduled maintenance to preserve high performance
standards, prolong the service life of the equipment, and
lessen the chances of costly failure.
In many instances the owner may be able to perform some
of the maintenance; however, the advantage of a service con-
tract, which places all maintenance in the hands of a trained
serviceman, should be pointed out to the owner.
WARNING
HIGH
VOLTAGE
D
ISCONNECT
ALL
POWER BEFORE SERVICING OR
INSTALLING THIS UNIT.
M
ULTIPLE POWER SOURCES MAY
BE PRESENT.
F
AILURE TO DO SO MAY CAUSE PROPERTY
DAMAGE, PERSONAL INJURY OR DEATH.
ONCE A MONTH
1. Inspect the return filters of the evaporator unit and clean
or change if necessary.
NOTE:
Depending on operation
conditions, it may be necessary to clean the filters more
often. If permanent type filters are used, they should be
washed with warm water, dried and sprayed with an ad-
hesive according to manufacturers recommendations.
2. When operating on the cooling cycle, inspect the con-
densate line piping from the evaporator coil. Make sure
the piping is clear for proper condensate flow.
ONCE A YEAR
Qualified Service Personnel Only
1. Clean the indoor and outdoor coils.
2. Clean the casing of the outdoor unit inside and out .
3. Motors are permanently lubricated and do not require
oiling. TO AVOID PREMATURE MOTOR FAILURE, DO
NOT OIL.
4. Manually rotate the outdoor fan and indoor blower to be
sure they run freely.
5. Inspect the control panel wiring, compressor connections,
and all other component wiring to be sure all connec-
tions are tight. Inspect wire insulation to be certain that
it is good.
6. Check the contacts of the compressor contactor. If they
are burned or pitted, replace the contactor.
7. Using a halide or electronic leak detector, check all pip-
ing and etc. for refrigerant leaks.
8. Check the combustion chamber (Heat Exchanger) for
soot, scale, etc. Inspect all burners for lint and proper
positioning.
9. Start the system, using the proper instrumentation check
gas inlet and manifold pressures, burner flame and
microamp signal. Adjust if necessary.
10. Start the system and run both a Cooling & Heating Per-
formance Test. If the results of the test are not satisfac-
tory, see the "Service Problem Analysis" Chart of the
possible cause.
TEST EQUIPMENT
Proper test equipment for accurate diagnosis is as essential
as regular hand tools.
The following is a must for every service technician and ser-
vice shop:
1. Thermocouple type temperature meter - measure dry bulb
temperature.
2. Sling psychrometer- measure relative humidity and wet
bulb temperature.
3. Amprobe - measure amperage and voltage.
4. Refrigeration Test Cord - check compressors, motors,
and continuity testing.
5
Volt-Ohm Meter - testing continuity, capacitors, and motor
windings.
6. Accurate Leak Detector - testing for refrigerant leaks.
7. High Vacuum Pump - evacuation.
8. Electric Vacuum Gauge, Manifold Gauges and high
vacuum hoses - to measure and obtain proper vacuum.
9. Accurate Charging Cylinder or Electronic Scale - mea-
sure proper refrigerant charge.
10. Inclined Manometer - measure static pressure and pres-
sure drop across coils.
Other recording type instruments can be essential in solving
abnormal problems, however, in many instances they may
be rented from local sources.
Proper equipment promotes faster, more efficient service, and
accurate repairs with less call backs.
COOLING & HEATING PERFORMANCE TEST
Package Cooling and Package Heat Pumps
Before attempting to diagnose an operating fault, run a Cool-
ing and/or Heating Performance Test and apply the results to
the Service Problem Analysis Guide.
Package Gas Units
Before attempting to diagnose an operating fault, run a heat-
ing performance test and apply the results to the Service
Problem Analysis Guide.
To conduct a heating performance test, the BTU input to the
furnace must be calculated.
After the heating cycle has been in operation for at least
fifteen minutes and with all other gas appliances turned off,
the gas meter should be clocked.
SCHEDULED MAINTENANCE
