so im new to this whole site and this is my first post. Im out of Ontario im a relatively new mechanic and my company has recently made a push into the supermarket refrig field, and ive already run into an issue that has seem to stump most people including hussman tech support.
Im getting ice build-up in the plenium of my case, and the ice will gradually build up until it stops the evaporator fan blades. But im getting a positive defrost off my coil, but the ice is not escaping the plenum and making its way to the trough at the front of my case.
These are refurbished freezer cases using 407A. im running them in a bank of 3 cases off a single sporlan EEPR valve, which is controlled by a einstein E2 controller. But my whole line-up is having the same issue.
The issue has been happening ever since construction was finished 6 months ago, and ive de-iced the coils 3 times since.
The cases have electric defost (3 daily at 55 mins. with a minimum of 40 mins.) I increased the defrost time and minimum to try and get more heat in the plenum. Ive verified with hussmans spec that all my heaters are in the exact place they should be. my superheat has been set. ive wedged up the plenum with washers but very minimal as to not affect the air flow when the fans are in refrig mode. i also have a slope to the front of my case so the water should be flowing to the drain.
My only guess at this point is that i have moisture between the bottom of the case and the isulation. Any ideas or has anyone seen this?