Way to test if your compressor is charged correctly.

[knotmeter]

If your cold plate is not zero degress or below then your freon is not adjusted properly or you need to add the duct kit to the compressor. This is how the service guy adjusted my unit. He put a temperature probe on the cold plate and had the temperature gauge up in the cockpit where he could see it while he adjusted the freon level. It took 4 or 5 hours to get it just right. Because as the temperature drops in the system it changes the dynamics of the freon level, so you have to keep adjusting it. Also it take that long for the box to cool down. But if its set correctly it makes a big difference. My cold plate before the adjustment was 15 degrees, afterwards it got down to minus 10. Which made the freezer go down to 27 degrees, before it was 39 degrees. I have one of those indoor/outdoor temperature gauges. I keep the external wire probe on the cold plate to tell me how the unit is running. This is a good way to test your unit to see if it needs adjusting.