Question 8Refrigeration & AC - 1st Asst/Chief

70% to pass

What would be an indication that the vegetable box back pressure regulator is set too low?

AVegetable refrigeration box is holding the correct temperature but the vegetables are dehydrated and frost is observed on the vegetable box evaporator coil back to the back pressure regulator.
BHigh discharge pressure on the compressor.
CVegetable box does not pull down to correct temperature and the compressor suction pressure is low.
DThe vegetable box is at the correct temperature and the compressor experiences short- cycling.
AI Explanation

The correct answer is A) Vegetable refrigeration box is holding the correct temperature but the vegetables are dehydrated and frost is observed on the vegetable box evaporator coil back to the back pressure regulator. This is the correct answer because if the back pressure regulator is set too low, it will cause the evaporator coil temperature to drop too low, leading to dehydration of the vegetables and frost buildup on the coil. The low back pressure also indicates the refrigeration system is not operating at the optimal pressure and temperature, even though the box may be holding the correct temperature. The other answer choices are incorrect because high discharge pressure (B), low suction pressure (C), and short-cycling (D) are not direct indicators that the back pressure regulator is set too low. These would be symptoms of other issues in the refrigeration system.

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