Question

Automatic expansion valve is also known as:

• A. Thermostatic expansion valve
• B. Float valve
• C. Constant pressure expansion valve
• D. Capillary tube

Hint:

Automatic expansion valve = constant pressure expansion valve!

Answer 1

The Correct Option is C

An automatic expansion valve maintains a constant pressure in the evaporator by adjusting the refrigerant flow rate.
It automatically opens or closes depending on the pressure, which keeps the evaporator pressure steady even if the load changes.
That is why it is also called a constant pressure expansion valve.
A thermostatic expansion valve works differently — it responds to the degree of superheat at the evaporator outlet.
A float valve regulates liquid levels, not pressure directly.
A capillary tube is a simple fixed restriction and cannot adjust flow automatically.
Therefore, the correct alternate name is constant pressure expansion valve.