What should not be done without determining the location of and repairing a system leak?

Adding refrigerant to a system without first determining the location of and repairing a leak is not advisable because doing so can lead to multiple issues. When a leak is present in a refrigeration or air conditioning system, adding refrigerant simply masks the problem without addressing the underlying issue.

If the leak is not fixed, the newly added refrigerant will eventually escape, leading to poor system performance, inefficiency, and can even cause damage to the compressor over time due to operating with insufficient refrigerant. Moreover, this practice can also be environmentally harmful, as refrigerants often contain substances that are regulated under environmental laws.

In contrast, changing the compressor, replacing refrigerant oil, or performing system maintenance all inherently involve a thorough assessment of the system's integrity, including locating and addressing any leaks. These actions would typically ensure that the system operates reliably and efficiently, preventing further leaks and maintaining safety and performance standards.