Apparently a familiy of rats decided the heater was a great home and destroyed the inside of the heater over the winter :-( Yuck and booo.... Pool technichian came out and told me it needs to be replaced. It is the 125,000 BTU version and the quote to replace it is around $3300. That seems high to me, am I wrong? How complicated it is to replace since all the connections already exist. Is it something I could do?