96
AGZ 026B through 130B
IOMM AGZ-5
Unit Maintenance
General
On initial start-up and periodically during operation, it will be necessary to perform
certain routine service checks. Among these are checking the liquid line sight glasses,
taking condensing and suction pressure readings, and checking to see that the unit has
normal superheat and subcooling readings. A recommended maintenance schedule is
located at the end of this section.
Compressor Maintenance
The scroll compressors are fully hermetic and require no maintenance other than
checking oil level.
Lubrication
No routine lubrication is required on AGZ units. The fan motor bearings are
permanently lubricated and no further lubrication is required. Excessive fan motor
bearing noise is an indication of a potential bearing failure.
Compressor oil should be standard refrigeration mineral oil such as Suniso 3GS.
Electrical Terminals
WARNING
Electric shock hazard. Turn off all power before continuing with following service.
Condensers
The condensers are air-cooled and constructed of 3/8" (9.5mm) O.D. internally finned
copper tubes bonded in a staggered pattern into louvered aluminum fins. Maintenance
consists primarily of the routine removal of dirt and debris from the outside surface of
the fins and repairing any fin damage. McQuay recommends the use of foaming coil
cleaners available at most air conditioning supply outlets. Use caution when applying
such cleaners as they can contain potentially harmful chemicals. Care should be taken
not to damage the fins during cleaning. The coils should be thoroughly rinsed to
remove any cleaner residue.
If the service technician determines that the refrigerant circuit contains
noncondensables, recovery can be required, strictly following Clean Air Act
regulations governing refrigerant discharge to the atmosphere. The Schrader purge
valve is located on the vertical coil headers on both sides of the unit at the end opposite
the control box. Decorative panels cover the condenser coils and must be removed for
servicing. Recover with the unit off, after a shutdown of 15 minutes or longer, to allow
air to collect at the top of the coil. Restart and run the unit for a brief period. If
necessary, shut the unit off and repeat the procedure. Follow accepted environmentally
sound practices when removing refrigerant from the unit.
Optional High Ambient Control Panel
Consists of exhaust fan with rain hood, two inlet screens with filters, necessary
controls and wiring to allow operation to 125
°
F (52
°
C). The option can be factory or
field installed as a kit. Must be used for:
•
Ambient temperatures above 105
°
F (40
°
C) with fan VFD (low ambient option).
•
Ambient temperatures above 115
°
F (46
°
C) with standard FanTrol control.
•
Check inlet filters periodically and clean as required. Verify that the fan is
operational.
Summary of Contents for AGZ026BS
Page 103: ...IOMM AGZ 5 AGZ 026B through 130B 103...
Page 104: ...104 AGZ 026B through 130B IOMM AGZ 5...
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