A restriction in the metering device can cause which evaporator condition?

• A. Overfed evaporator
• B. Increased efficiency
• C. No effect
• D. Starved evaporator

Answer: (D)

A restriction in the metering device reduces the flow of refrigerant into the evaporator. With less liquid reaching the evaporator, there isn’t enough refrigerant to absorb heat effectively, so the evaporator becomes starved of liquid. This lowers cooling capacity and keeps the evaporator running warmer than it should. That’s why the proper description is a starved evaporator. A restriction wouldn’t increase flow or efficiency, and it wouldn’t have no effect—the cooling performance would decline as flow is restricted.