Frost accumulation occurring on a refrigerator evaporator coil results in________________?
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Answer: A. results in loss of heat due to poor heat transfer
Explanation
Frost acts as an insulating thermal barrier on evaporator coils, reducing heat transfer efficiency. Ice has a relatively low thermal conductivity compared to clean copper or aluminum evaporator tubing. This thermal resistance prevents ambient heat from properly entering the refrigerant inside the coils. Moisture from humid air condenses and freezes upon striking evaporator surfaces below zero degrees. Accumulated frost layer thickness increases the overall thermal resistance of the heat exchanger wall. Reduced heat absorption forces the compressor to run longer cycles to achieve required cooling.
Commercial refrigerators and heat pumps incorporate automatic defrost cycles to maintain optimal operation. Neglecting frost buildup leads to severe drops in cooling capacity and increased electricity bills. Maintaining clean evaporator surfaces ensures efficient thermal performance in domestic kitchen appliances. Increasing heat transfer rate is incorrect because frost acts as a thermal insulator. Frost accumulation is never immaterial as it degrades system efficiency and cooling capacity. Proper design can manage frost formation but cannot completely prevent moisture deposition from air.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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