My Carrier Infinity has a 50psig low pressure cutout. When the tech did a pump down a couple of weeks ago, to replace my evaporator, I noticed that he didn't bypass the cutout, and I don't think he even let it get to 50psig before manually flipping the breaker. He did appropriately recover any remaining 410a.
When he was back today, I asked him about that and he says that he doesn't bypass the low pressure cutout, because of the risk.
This was also the same tech that told Carrier he had no problem pumping down the compressor (Carrier was trying to rule out compressor issues).
My question is, if you don't let the compress pump down below the 50pisg cutout, can you really say that a compressor successfully passes a pump down test?