Unicla UWX440, Installation Manuallines

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8. Compressor sight glass visualisation and diagnosis
The following chart and images will assist the technician to check the sight glass of the compressor
after commissioning of the system. Different operating conditions will present variable symptoms
to appear at the sight glass, and Unicla recommends this must be checked immediately after
commissioning and at future regular intervals during service.
To obtain the best possible visual of the sight glass, it is recommend the rear sight glass is back lit
with a good quality white light , preferably from a LED torch or leadlight. This will produce good
light through the centre of the compressor sump to allow accurate evaluation of the compressor
level and quality.
Sight Glass Normal > high point
Oil Normal - clean and transparent
Operation OK
Recommendation Nil
Sight Glass Normal > high point
Oil Slight moisture contamination - orange to brown colour
Operation OK
Recommendation Monitor oil condition and change if necessary
Sight Glass Normal > high point
Oil Green colouration - exposure to copper oxidation
Operation OK
Recommendation Monitor oil condition and change if necessary
Sight Glass Oil level low < half point
Oil Normal - clean and transparent
Operation Oil flow or level is low
Recommendation Check suction pressure and system oil quantity
Sight Glass Oil level low < half point
Oil Normal - clean and partly transparent
Operation Oil flow or level is low and running at high temperature
Recommendation Check suction pressure and system oil quantity
Sight Glass Normal > high point
Oil Black and cloudy - severely contaminated
Operation Compressor will fail
Recommendation Cease system operation - clean and flush system, replace compressor oil
Sight Glass Oil level < high point
Oil Black and cloudy - foaming and severely contaminated
Operation Compressor will fail
Recommendation Cease system operation - clean and flush system, replace compressor oil
Sight Glass Oil level < low point
Oil Not visible
Operation Oil flow or level is criticaly low - damage to compressor will occur. Suction
pressure is most likely at 1.0 bar (14 psi) or less and must be rectified
Recommendation Cease system operation and check suction pressure and system oil quantity
6.