Hotel Service Unit 11 Q8 Quiz

Correct Answer:
A) It regulates refrigerant flow based on temperature and pressure changes

Explanation:
The diaphragm in the expansion valve responds to pressure changes created by the thermal bulb and spring, adjusting the valve opening to regulate refrigerant flow according to evaporator conditions.

Correct Answer:
A) It closes slightly to reduce refrigerant flow

Explanation:
If the evaporator temperature drops, the thermal bulb reduces the pressure on the diaphragm, causing the valve to close slightly. This limits refrigerant flow and prevents excessive cooling in the evaporator.

Correct Answer:
B) Thermal bulb

Explanation:
The thermal bulb is a key component of the thermostatic expansion valve, sensing temperature changes in the evaporator and adjusting the valve opening to control refrigerant flow.

Correct Answer:
B) To prevent the evaporator from freezing or overheating, maintaining efficient cooling

Explanation:
By controlling the refrigerant flow, the expansion valve prevents both freezing and excessive warming in the evaporator, allowing it to maintain efficient heat absorption.

Correct Answer:
C) The valve opening increases to allow more refrigerant to enter

Explanation:
If the evaporator temperature rises, the thermal bulb signals an increase in pressure on the diaphragm, opening the valve wider to let more refrigerant flow and absorb more heat, thus cooling the evaporator.

Correct Answer:
B) Spring

Explanation:
The spring applies opposing pressure to the diaphragm, balancing the force from the thermal bulb to maintain the correct refrigerant flow rate.

Correct Answer:
B) By sensing the evaporator outlet temperature and sending a pressure signal to the diaphragm

Explanation:
The thermal bulb, placed at the evaporator outlet, senses temperature changes and adjusts the pressure in the diaphragm chamber. This pressure shift modulates the valve opening to control refrigerant flow.