AC leaking refrigerant

Anyone know whether or not the AC compressor could leak out all the refrigerant without anything showing on a dye-test. This has happened twice within a 6 week span and dye-tested twice. A repair shop finally used a sniffer to detect a leak in the evaporator, but that doesn’t really answer why a compressor would need to be replaced if there was no evidence of leaking and it was functionally working.

If the evaporator is the only thing that’s leaking, there’s no reason to replace the compressor.

Tester

Just to clarify, if possible. Can the compressor be leaking if there is no evidence with dye-testing and all of the refrigerant is lost in 2-3 weeks? There doesn’t seem to be much of anywhere to leaking other than the couplings for the lines. I don’t think the compressor itself would be leaking, at least not at that rate. I agree that if the sniffer shows the evaporator is leaking I will need to replace it, but I want to be relatively sure that there are not additional problems that will also need to be repaired. Just the cost of replacing the evaporator is pushing the limit based on the age and miles, so I am not sure that I also want to spend even more on the compressor. I appreciate your response.

The compressor can leak at the shaft seal. And if it is the refrigerant sniffer will easily detect this.

Tester