Mazda - Miatamx-5 :: Air Conditioner Keeps Blowing The High Pressure Hose

My car is a 2006 Mazda Miata, stock except for being lowered and having a different muffler. Nothing really noteworthy about it. I did run over a big chunk of something a few years ago that cracked the plastic undertray under the nose of the car and dented the bottom row of the condenser, but the problem I'm having is more recent.

About a year ago the AC stopped working. I took it to one shop that found there was no refrigerant in the system. They refilled it, and a few hours later it stopped working again. I took it to another shop that detected a leak in one of the schrader valves (the low pressure I think). He replaced that, filled it, and it worked again for another few months.

Recently it stopped working again. I took it to the same guy that replaced the schrader valve and he found that the high pressure hose had failed. He replaced it and refilled the system. It worked for a few hours. Then when I was sitting at a drive thru, a massive cloud of refrigerant erupted from under the hood and the AC stopped working. Took it back to the guy and he found the high pressure hose had blown off. He put it back on, refilled it, and the same thing happened again. Sitting in traffic, the high pressure hose blew and all the refrigerant poured out.

I took it back to him again and he put the hose back on and refilled it again. We let the car idle for about 30 minutes with the AC on and it worked fine. During this he had the high pressure gauge hooked up and it read between 150 and 175 with the car idling (about 70 degrees F ambient temp). He didn't have the low side gauge hooked up. We did see that the fan is working and kicked up to the higher speed. He did say he checked the dryer and that it looked like the bag that held the desiccant was intact, but he didn't mention replacing the dryer in any of these visits.