Question 127Refrigeration & AC - 1st Asst/Chief

The correct answer is B. The illustrated thermal expansion valve type B would be the most appropriate choice for an evaporator coil with a 2 psi pressure drop, as it provides externally adjustable superheat and a replaceable power element, which are both desired features in this application. The other options would not be as suitable - type A lacks external superheat adjustment, type C does not have a replaceable power element, and type D is typically used for higher pressure drop applications.