Need to check not guess its easier than guessing and rigging too. But i had the same thing on a b model i had to replace the HPR valve... but you also need to check the TXV bulb. What is the discharge temp and HPR inlet valve temp 5 in freeze and the end?
Well, 2 weeks ago i replaced the leaking LP switch. At that time i figured that was the cause of the 4 blink safety shut down. Recovered only 9lbs. Should have had 13lbs. But anways, i went back to the place Tuesday to work on a cooler and i check on the ice machine and its down again. Same 4 blink safety. Couldn't work on it. But i did fire it up and it ran for about 30 seconds and tripped again. I'm gonna head back there when i get a chance. First thing i'll do is check actual discharge temp and go from there. Before i found and repaired the leak. I never saw discharge temps exceed 250. It only tripped after i was gone and maybe 2 days later. I really thought the leak was the problem but now i guess it was not.