CFC Industry Exam with Complete Solutions

What is CFC? - ANSWER-Chlorofluorocarbon What is HCFC? - ANSWER-Hydrochlorofluorocarbon Evaporator coil replacement is Always considered major repair. - ANSWER-1 Recovery/recycling equipment manufactured BEFORE Nov 15, 1993 must evacuate low pressure appliances to 25 hg vacuum. - ANSWER-2 Wait a few minutes to see if pressure rises indicating refrigerant in liquid form or in oil after reaching required recovery vacuum. - ANSWER-3 Refrigerant vapor reintroduced before liquid chraged into deep vacuum will boil and may lower temp. to cause water to freeze in tubes. - ANSWER-4 Leaks in appliance make evacuation to perscribed level unattainable so appliance need not be evacuated all the way. - ANSWER-5 Recovery/recycling equipment manufactured AFTER Nov. 15, 1993 must be evacuated to 25mm hg absolute. - ANSWER-6 When leak rate exceeds 35% charge per year EPA regulations require commercial/industrial process be repaired. - ANSWER-7 R11, R123 refrigerant removal starts with liquid removal. - ANSWER-8 Place leak detector probe through drain valve to check gas leaks into water box with water removed. - ANSWER-9 Appliances containing more than 50lbs of refrigerant (except commercial/industrial) required to be repaired when leak rate exceeds 15% of charge per year. - ANSWER-10 Raising pressure with circulated hot water or heating blankets is the most efficient way to leak check a charged low pressure refrigeration machine. - ANSWER-11 Hydrostatic tube test kit determine if tube leaks. - ANSWER-12 Add nitrogen to pressurize R11 or R123 system for purpose of opening for non-major repair. - ANSWER-13