(a) What are the reasons for foaming in refrigeration compressor crankcase? (4)

(b) Describe the causes for the following in the domestic refrigeration system: (12)

(i) Frequent cut-in and cut-out of the compressor.

(ii) Low oil pressure cut-out of the compressor.

(iii) High pressure cut-out of the compressor.

(iv) Frosting in the compressor suction side.