Desert Aire Aura QS, Installation And Operation Manual

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5 Appendix
5.1 Compressor Failure
Although some compressors fail because they are mechanically flawed, most failures are due
to system-related problems. Compressor failure can be caused by liquid flood back,
air/moisture in the refrigeration system, solid contaminants, excessive heat or electrical service
malfunctions. To avoid repeated callbacks, you must determine the cause of the failure and
then correct it.
If the compressor has failed because its motor has burned out, the refrigerant, oil, and piping
may have become severely contaminated. If a burnout has occurred, use the following
procedures to replace the compressor and clean the refrigerant system. Use an oil test kit to
determine the severity of the burnout. Make sure you use rubber gloves and eye protection,
as contaminated refrigerant and oil can cause severe burns!
You must clean the system thoroughly to prevent repeated compressor burnouts.
5.1.1 Compressor Replacement
Desert Aire dehumidifiers are designed with scroll compressors. Scroll compressors
are known for operating more reliably than other compressors in air conditioning and
dehumidification applications due to their ability to cope with occasional periods of
liquid refrigerant return. There are fewer moving parts in a scroll compressor subject
to wear compared to alternative compressor designs. Nonetheless, there are still
many mechanical and electrical parts with close tolerances. Replacement of the
compressor may be required during the normal service life of the dehumidifier.
Inspection and Initial Diagnosis
Generally, the compressor will have two basic failure modes, mechanical or electrical.
The compressors are a hermetic design, meaning all components, including the
motor, are in a sealed shell. It can be very difficult to determine which issue was the
root cause of the failure in the field by inspection of the damaged compressor. For
example, an initial bearing failure inside the compressor may create debris that
contaminates motor windings. High current draw may be related to a bearing issue
or a motor winding issue. The initial inspection must be combined with a final analysis
of the machine when returned to working order to confirm diagnosis.
Specific items should be noted before the replacement to give the best indications of
the failure and complete the diagnosis as the new compressor is installed.
Desert Aire - QS/QV Manual