DESCRIPTION OF COMPRESSOR FEATURES (Continued)
Automatic Reversible Oil Pump To provide full volume and pressure regardless of motor rotation.
Oil pump is positive displacement vane type pumps. Pump produces high volume oil flow at low
Suction and Discharge Valves of Swedish Steel Both valves could operate 2 1/2 million times per
day. Swedish steel is finest available anywhere for this application and is designed to handle some
oil and refrigerant slugs.
Main bearings and Running Surface Steel Backed Aluminum or Tin Base Babbitt-Aluminum or tin
based babbitt material used on bearing surfaces provide greater load carrying ability than other
materials and are less susceptible to damage from overheating or liquid refrigerant.
COMMENTS ON COMPRESSOR LUBRICATION
All refrigeration compressors must have adequate lubrication to ensure trouble-free operation and a long life.
On the start-up of any new system, some oil will be lost to coat the inside of the piping, some lodged in low
velocity areas of the system after the initial start-up, for very low compressor oil levels can cause complete loss
of lubrication and will result in an immediate compressor failure if it is not protected.
The loss of oil can also be caused by flooded starts refrigerant migrating to the oil during an off period and
pulling the oil out of its sump during the sudden pressure drop of a start-up.
The level should be observed in the sight glass while the compressor is running. The level observed when the
compressor is not running may be a mixture of oil and refrigerant, which would not be a true indication of the oil
level when the compressor is running. Note that the sight glass is a prism type, with vertical or circular lines
which can be seen in the glass when the oil level is below the bottom of the glass. If no oil level is observed
and the vertical or circular lines cannot be seen, the oil level is above the top of the sight glass.
If the oil level in the sight glass is less than one-eighth (1/8) up from the bottom of the glass, this indicates a low
oil level. If the oil level is up more than one-half (1/2) from the bottom, this indicates a high oil level.
Therefore, the oil level should be 1/8 to 1/2 up the sight glass when the compressor is running.