My Pentair MasterTemp 400 is in its 7th full season of use and has been leaking water for a few weeks. I finally removed one of the access panels and sure enough, the bottom of the combustion chamber/"tub" is heavily rusted. I have a salt pool, and while I maintain my salt level around 3600 and pH between 7.4-7.8, I guess time took its toll on the copper heat exchanger long ago, and the leak finally ate out my combustion chamber as well. It probably didn't help that my builder didn't install a bypass valve, so flow was constant and eroded the heat exchanger even when the heater wasn't in use. Quick questions:
I have a 17,500 Gal inground pool. After checking the specs on a 250 BTU unit, I think that will suffice. The 400 BTU was probably overkill on a pool my size - thoughts?
I plan to buy an HD model with a cupro-nickel heat exchanger. It appears that regardless of BTU rating, models equipped with a cupro-nickel heat exchanger cost $300+ more than those with copper heat exchangers. I've read it's well worth the investment, especially with a salt pool. Thoughts?
Finally, and what should probably be my first question: would it be more cost-effective to replace the heater, or to just have the unit serviced and the heat exchanger and combustion chamber replaced? Dumb question since I haven't asked for a bid, much less called for service, but wholesale prices on the heat exchanger and combustion chamber total $750+, and I'm sure the additional labor for repair versus installing a replacement unit will add another $200-300.
I appreciate any advice, and thanks,