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Why heaters are provided in the crankcase of a refrigeration compressor?

a. To avoid carry over of the lube oil because at low temperature, the separation of the 
refrigerant and the oil is difficult 
b. To condition the lube oil, by maintaining the viscosity so that the lubrication is 
effectively carried out. 
c. This prevents the lube oil achieving its floc point which may cause narrowing or 
chocking of the passages (flocculation)


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