Desert Aire Aura QS, Installation And Operation Manual

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The following data should be taken to assist in diagnosis:
• Current draw for each leg of power (if the compressor will run and pump).
• High side and low side pressure (if the compressor will run and pump).
• Resistance of each leg to leg on three phase compressors or each leg to
neutral on single phase compressors.
• Check of continuity from each leg to ground.
• Review of all system alarms including the relative timing of the alarms and
mode of operation.
It is important to note that other components or lines may have been damaged if the
compressor has failed. At times the internal damage to a compressor creates extreme
levels of vibration before complete failure. Refrigerant lines and connections may be
damaged before the compressor stops. Inspect tubing and components of the system
before completing the compressor replacement.
Compressor Replacement
• Refrigeration oil must be tested for acid and particulate during any compressor
replacement. For the initial testing, the compressor sump should be used to
sample the oil. Oil can be recovered through the Schrader port on the low
point compressor shell or through the suction line connection after the
compressor has been removed.
• Use Virginia KMP, New-Calgon Phase III, Sporlan Test-All, or equivalent oil
test where oil is sampled into a container. Vapor sampling methods may not
show particulate and should not be used.
• Read the oil test kit manufacturer’s instructions to determine if there is acid
present in the oil. Determine if there are other contaminants by viewing the
samples for darkness, cloudiness, or particulate.
The following procedures must be used depending on the results of the test above:
Any Compressor Service
• A new filter dryer must be installed when the system has been opened. If
there is no acid or particulates indicated, the new compressor can be installed
and run. Proceed to Testing and Final Diagnosis.
Desert Aire - QS/QV Manual