A commercial display freezer's low-pressure switch is consistently tripping, causing the compressor to short-cycle. The system uses R-404A. If the cut-out setting is 120 kPa and the cut-in setting is 210 kPa, which of the following could indicate an issue if the ambient temperature is 20°C?

Question: A commercial display freezer's low-pressure switch is consistently tripping, causing the compressor to short-cycle. The system uses R-404A. If the cut-out setting is 120 kPa and the cut-in setting is 210 kPa, which of the following could indicate an issue if the ambient temperature is 20°C?

Answer options: ✅ The evaporator coil is heavily iced up.

• The condenser coil is dirty.
• The high-pressure switch is improperly set.
• The defrost heaters are operating correctly.

Correct answer: The evaporator coil is heavily iced up.

Explanation: Heavy icing on the evaporator coil restricts airflow and heat transfer, leading to a significant drop in suction pressure within the system. This lower pressure can fall below the cut-out setting of the low-pressure switch, causing it to trip and cycle the compressor off.