Question 98Refrigeration/AC - Assistant Engineer70% to pass
When pumping down an air conditioning system to test the low-pressure cutout switch, assuming that the compressor is running, what should be done to initiate the test?
AI Explanation
The correct answer is C) close the 'king' valve.
To test the low-pressure cutout switch, you need to reduce the pressure in the system. Closing the 'king' valve, which is the valve that isolates the compressor from the rest of the system, will cause the pressure to drop and allow the low-pressure cutout switch to activate. This is the correct way to initiate the test without affecting the operation of the compressor or other components.
The other options are incorrect because: A) securing the condenser would not affect the pressure in the system, B) stopping the compressor would not allow you to test the low-pressure cutout switch, and D) stopping the circulating pump would not directly impact the pressure in the system.
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