Seems you need replace the whole system since it is already 14 years old as in your post below.
But what if something wrong with a 5/6 year units?
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There is not much those AC guys could do for the leak if it was a a simple problem, i.e. valves or pipe joint not tighten up. Obviously you should replace the whole system for the 10+ year unit.
But what if something wrong with a 5/6 year units?
Now you will realize JY101 is right. Use the most common and cheaper brand. The system is simpler than the high end units. If the problem could not be easily fix, just replace the problem parts, i.e. compressor, coils.
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