I have a two year old Jandy pool heater. The heater stopped working several days ago. Pool service guy said it’s a leaking heat exchanger and will need to be replaced. He’s going to call with a price because that part is not covered by warranty. He mentioned it’s highly susceptible to damage by water chemistry. By my quick scan online scan, seems this is going to be an expensive fix. We will soon NEED a heater to use the pool, so will have to go through with the repair, but my question is why it is leaking and what I can do to prevent in the future. Is the leak a random thing or could it really be caused by water chemistry? I worked hard this season to keep water chemistry in check. Appreciate any/all input.