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

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

(i) Frequent cut-in and cut-out of the compressor. (3)

(ii) Lub oil low pressure cut-out of the compressor. (3)

(iii) High pressure cut-out of the compressor. (3)

(iv) Frosting in the compressor suction side. (3)