Question 198Refrigeration/AC - Assistant Engineer70% to pass
What is true concerning frost build-up on the evaporator coils of a multi-box direct expansion refrigeration system?
AI Explanation
The correct answer is A.
The frost build-up on the evaporator coils of a multi-box direct expansion refrigeration system can be removed by passing hot gas through the coils or energizing defrost heaters with the evaporator fan shut down. This is the standard method for defrosting the evaporator coils in such a system. Shutting down the compressor (option D) would not effectively remove the frost, and the frost build-up would actually decrease the refrigeration effect (option C is incorrect).
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