Dear Mr. Arendes:
Thank you for writing to me. I hope that you and your family are well. When you have a copper nickel heat exchanger if you have a chemical imbalance or a PH variation it can attack the heat exchanger. I have seen them last 3 months. With that water I could feel it burning my cuticles on my fingers. I also have some that are still going strong after 24 years. If you get a heater with a titanium heat exchanger then nothing in a pool can hurt it. Water freezing in the winter will void a titanium one though. I would reach out to them again. Maybe ask for a supervisor. Maybe they will split the cost of the repair with you or try to make an accommodation. They are a respected company and I would think would want to help. Court is probably not the best option. It is better to work it out. They will probably prove that chemicals ate the metal. When anyone mentions lawyer when dealing with the big pool companies they just turn it over to their in house people and all help stops.