Moisture in the refrigeration system can also cause which of the following?

• A. Acid formation in the system
• B. Metering device freeze-up
• C. Grounding on the compressor
• D. Filter blockage

Answer: (A)

Moisture in a refrigeration system reacts with the refrigerant and the oil at operating temperatures to form acids, such as hydrofluoric and hydrochloric acids. These acids attack copper and aluminum components, corrode fittings, and degrade the lubricating oil, which can lead to increased wear, sludge, and eventual leaks or compressor failure. This direct production of corrosive acids is the most impactful and common consequence of moisture, which is why it’s the best answer.

Metering device icing can occur under certain low-temperature, high-moisture conditions, but it’s not the primary problem moisture causes. Grounding issues are electrical and not caused by moisture in the refrigerant loop, and filter blockage is more a result of sludge or debris forming after acid and contamination develop rather than the moisture itself.