I am designing a refrigeration plant with single vertical plate freezer.
I am not sure how to design defrosting, since it is only one unit in the system, and I do not know how to provide hot gas for defrosting.
I have got some advices to install additional small air evaporator in space nearby, to provide hot gas, but I actually do not know how big it should be, and anyway I do not need it, have nothing to cool.
The system will be liquid overfeed with pump.I would prefere to use R404a, but I am avare of problems with oil managment. If somebody has experience, please help

I have experience with plate freezer and ammonia installation with hot gas defrosting, but it was always with several evaporators in system, and supplying hot gas was never problem.

Thank you in advance.