IPhone 6 16GB Verizon won't turn on at all?

I have a iPhone 6 16GB with Verizon and it doesn't turn on at all. I tried charging it, nothing. I even replaced the battery and the charging port as well, nothing. I check to see if the Water damage indicator was red and it isn't. I'm starting to run out of ideas. What could it possibly be? Any info would be much appreciated!

Possibly your charger is bad. And if it is bad charger the battery might of went completely dead. So id try different charger n leave it plugged in for 3 or 4hrs or more to see