Which indicators signal moisture in a refrigeration system and how can moisture compromise performance?

• A. Cloudy oil, acid formation, corrosion, and acid odors
• B. Clear oil and absence of odors
• C. High refrigerant charge
• D. Bright green oil

Answer: (A)

Moisture in a refrigeration system shows up as cloudy oil, acid formation, corrosion, and acid odors. Water in the system reacts with the refrigerant and lubricating oil when the system is under heat, creating acids and emulsions. The oil becomes cloudy as water droplets are dispersed, and acids form and can produce noticeable odors. Those acids attack metal surfaces and fittings, causing corrosion, and the presence of acid smells confirms a corrosive, acidic environment inside the circuit. Together, these symptoms are reliable signs of moisture contamination rather than normal operation.

Moisture undermines performance in several ways: it degrades lubrication by breaking down oil, accelerates corrosion of copper and steel components, promotes sludge and deposit formation that can clog filters, strainers, and metering devices, and can freeze in narrow passages like capillary tubes, restricting refrigerant flow. All of these effects reduce efficiency, increase wear, and can lead to compressor damage.