My dog is destructive

Last year I adopted a puppy.

I have always been an animal lover and I love both dogs and cats.

It was going well for a while until one day my dog started becoming fascinated with my portable air conditioning system. It was a window AC system and yet for some reason my dog wanted a piece of it. Problems began because my dog started to see the air conditioning system as a chew toy. I loved that air conditioning system and so I had to go out of my way to protect the AC unit from my dog. My dog would go and do everything he could to get to that air conditioning system. I would set it up high and I would literally find him jumping trying to get to it. And why my dog was doing this, he had plenty of two toys and I gave him lots of attention and yet for some reason he still wanted to show my air conditioner. He had already been someone successful because there was a couple times I forgot to put the air conditioner away and I would have found him with it in his mouth chewing on it. My poor window air conditioning system now has a bunch of permanent shoe marks on it that I will not be able to remove. And I don’t really want to go and buy another window AC. I’m starting to think maybe it’s my fault and I haven’t just trained him enough and I’m thinking about taking some dog training classes. I love my dog very much, but I hope that he can beat this bad habit.
Air conditioner tune-up