I do not know what the records look like for this pool. I used to do heater installs for this pool service company but after issues with them I quit doing anything with the company.
YippeeSkippy, I can replace the heat exchanger and it would be good. P&L is over $1K. I did verify that it still fires. Leak is on the back corner so pilot assembly is in good shape. Homeowners never did check behind the service company to see if they were doing their job. Kind of sad companies don't do what they are hired to do. It takes very little time to manage a pool properly.
Side note. The same pool service company the day before told another customer that she needed to replace the board on her Easytouch system because ants had gotten on it and shorted it out. Customer had complained to them that the pool wasn't coming on at its normal time. I also installed her heater so she called me to look at the controller issue. Yes there were a few ants on the board but I've never seen an ant short a board. 2 ants is all I found. However, when I went in her house to look at the controller on the wall I noticed the time was on AM when it should have been on PM. She set it wrong when we had the time change. Pool has been running on schedule ever since.
Not all pool service companies are like this. But if you do use one, sometimes you have to question them and don't always take their word for things that might be wrong. Like many pool stores, they make more money off repairs and selling you chemicals.