What is the maximum moisture content allowed in recycled R-134a intended for mobile air-conditioning systems?

The correct answer is that the maximum moisture content allowed in recycled R-134a intended for mobile air-conditioning systems is 50 PPM (parts per million). This specification is critical for ensuring the efficient and effective performance of air-conditioning systems. Excess moisture in refrigerants can lead to various problems, including corrosion of components, degradation of lubricants, and formation of acid, which could negatively affect the system's longevity and efficiency.

The standards for moisture content in refrigerants like R-134a are established to maintain system integrity and operational reliability. Keeping moisture levels below 50 PPM ensures that the refrigerant remains stable and does not introduce moisture-related issues into the air-conditioning systems during operation. This helps in maintaining optimal performance and prolonging the life of the components involved. Such stringent limits are essential, especially in mobile air-conditioning systems, where reliability and performance are paramount.