Under what condition must the owner keep records of refrigerant added to a low-pressure system?

The requirement for owners to keep records of refrigerant added to a low-pressure system is specifically set at 50 pounds or greater. This regulation is designed to ensure that proper documentation is maintained whenever refrigerant is added to these systems, which is crucial for monitoring potential leaks and ensuring compliance with environmental laws. Keeping records helps in tracking the amount of refrigerant used, which assists in both efficiency and regulatory adherence.

Additionally, maintaining accurate records becomes increasingly important as it can help in assessing whether the system is operating correctly and within legal limits. Systems with a charge of 50 pounds or more are subject to these documentation requirements due to their potential environmental impact should leaks occur, thus necessitating monitoring to conform with established guidelines.