Hi guys, I have a blast freezer (-35°C) evap with some damage on it and would appreciate if I could get some ideas on what may have caused it?

There are numerous pockets of damage that seem to have 'blown' out from along the electric defrost bars (you can see the heater bar in the middle of the photo), taking the fins and copper pipes with it. I have been told it is from ice damage but my understanding is that ice build up would be randomly distributed. All of these pockets (about 8) have radiated from the heaters.

I hope you can see the damage clearly, if not I can try and get some other photos if that would help.

Thanks in advance,

Gareth

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