I have had some limited experience in refrigeration (commercial) but not a lot and all the stuff I learned in school is lost in the abyss.
Here is the problem. I have an APEX walk-in cooler and the evap coil is freezing from the bottom first then slowly creeping up. It is a fairly new system.
First I checked the pitch of the drain pan. Everything is fine, it drains to a secondary drain pan that the high side runs through to evaporate it.
Both fans are working correctly and the pressure is fine. I adjusted the defrost parameters so that the drip time after defrost is longer to facilitate proper drainage.
I am going back to check it first thing Monday morning. I suspect the TXV, however I don't remember what I am looking for. Am I barking up the wrong tree, or have I fixed the problem already?
Help, I HATE repeat calls. If the answer is already posted somewhere else let me know?