Question 12Refrigeration & AC - Assistant Engineer

The correct answer is B) the same refrigerant as the system. The thermal bulb of the thermal expansion valve is charged with the same refrigerant used in the air conditioning system. This allows the thermal bulb to accurately sense the temperature and pressure of the refrigerant, enabling the valve to properly regulate the flow of refrigerant into the evaporator. The thermal bulb needs to respond to the same conditions as the rest of the refrigerant system in order to function effectively. The other options are incorrect because beeswax, mercuric sulfate, and distilled water would not accurately reflect the temperature and pressure of the refrigerant, and would not allow the thermal expansion valve to operate as intended.