10 ft deli box with static coil old R-12 sys.

[supernova]

I have a deli box that use to have r-12 in it and it worked beautifully. The one day I was on vacation and compressor went, somebody else came out installed new semi-hermetic copeland, txv, and installed r-414b refrigerant in it. Unit has been this way for over a year and a half now and owner just tells me now that box works ok during winter but only maintains 45-50 degrees during spring and summer. I cleaned outdoor coil and adjusted charge by sightglass. I was told sightglass is not to be full, but bubbly and full off and on which it is now. Temperature has no change and coil is extremely wet, not frosty like it use to be. My question is would R-409a be a better choice? I know about the higher discharge Temps. Going to try this weekend.

[hd88]

414b "hot shot" is better than 409 in my opinion. In any system you need a full column of liquid to that txv, so get the vapor out of that sightglass and put more gas in it no matter what r12 drop in you use. and set the SUPERHEAT!!!!!!!!!!!!

[hd88]

Static coil superheat 4 to 6 degrees.