A small obstruction at the thermostatic expansion valve inlet will result in which of the following conditions?

Official USCG Answer & Rule Citation

Correct Answer: Option C — Lower than normal suction pressure.

A partial obstruction at the thermostatic expansion valve inlet restricts refrigerant mass flow into the evaporator. This starvation reduces the rate of vaporization, dropping the low-side boiling point and resulting in a lower than normal suction pressure on the compound gauge.

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