4 ton rudd 410 a/c installed by me a certified tech with an epa license. Freezes up once every six to twelve months. Supply duct sizing is adequate and it has a 24"x24" return should be adequate. Coil is clean and filter. All motors and compressor functioning correctly when freeze up starts. Abnormal finding I can not get the low side pressure above 105 psig which correlates to 32-34 degrees Fahrenheit. This is why I think when there is a slight temp change outside it's just enough to freeze it. If I try to charge the high side will continue to go up but the low side stays the same. My thought are possible restriction in the txv or maybe not enough air flow to the coil. I have tried removing the filter and changing the blower fan speed. Still the problem persists. Supply air is at 48 degrees Fahrenheit and return is around 70 Fahrenheit. New copper was used on install that was properly sized. Any help is appreciated.

Career

From the info you posted, I would definitely start with the txv. Also could be restricted drier filter. Im assuming the system was purged with nitrogen while brazing, and vaccumed to at least 500 microns. With 410a, if the system is not purged with nitrogen durning brazing, it is likely the txv, or filter drier, or both are partially plugged.

If everything was done correctly, then I feel your pain, as these symptoms can be a real bear to figure out. Wish you the best of luck, and please do let me know what you find.