Howdy group. You have all been a great help for me to learn about pool chemistry and equipment, so I got another question.
I had a pool company out today to service my pool heater. It's a typical Raypak style heater. I have been having issues with flakes of something coming out of my returns into the pool. Then, last year my heater was making a loud screeching noise, which turned out to be flakes clogging up the heater tubes, reducing the water flow, and even causing the pump to extra hot. They clean it out and it was fine. I had them back out to clean it this spring as I notices more flakes in the pool, although the tubes were fairly clear. In the process, I took some flakes and dumped a bit of muriatic acid on it and they fizzed like crazy, which I understand means it was mostly calcium scale. I have some left that I was going to try and test if there is any phosphate scale but I don't have a phosphate test kit yet. As a note, I have really high phosphates normally due to using metal magic for high iron.
However, the flakes have a copper color to them, and some of it that was copper colored did not dissolve in the muriatic acid. The pool guy ran a water test and calculated what he called LSI - Langelier Saturation Index. I assume from reading that this is basically the same as CSI that Pool math uses. His calc and Pool math both come in around a -0.8. The pool guy believe that the low LSI / CSI, or something, is causing the copper tubes in the heater to degrade and suggested raising pH to 7.6 / 7.8 with goal of a LSI / CSI between -.3 and 0.0, but trying to avoid going over zero which will just worsen the calcium flaking issue.
Also, I do NOT have a bypass system set to bypass the heater. Pool guy suggested it for any time using an AA treatment, although figuring out how to rework the plumbing given the room will be an issue.
This all sounds reasonable, but I wanted your input. My question is if there could be actual copper from the heater tubes flaking off and if a low CSI could be a cause of that. Or, if the CSI isn't the issue and the issue is the lack of a bypass. My goal is to lengthen the life of the pool heater as long as I can as I have to replace the liner at some point due to excessive wrinkling, and I need a new auto cover soon, and and and.
I had a pool company out today to service my pool heater. It's a typical Raypak style heater. I have been having issues with flakes of something coming out of my returns into the pool. Then, last year my heater was making a loud screeching noise, which turned out to be flakes clogging up the heater tubes, reducing the water flow, and even causing the pump to extra hot. They clean it out and it was fine. I had them back out to clean it this spring as I notices more flakes in the pool, although the tubes were fairly clear. In the process, I took some flakes and dumped a bit of muriatic acid on it and they fizzed like crazy, which I understand means it was mostly calcium scale. I have some left that I was going to try and test if there is any phosphate scale but I don't have a phosphate test kit yet. As a note, I have really high phosphates normally due to using metal magic for high iron.
However, the flakes have a copper color to them, and some of it that was copper colored did not dissolve in the muriatic acid. The pool guy ran a water test and calculated what he called LSI - Langelier Saturation Index. I assume from reading that this is basically the same as CSI that Pool math uses. His calc and Pool math both come in around a -0.8. The pool guy believe that the low LSI / CSI, or something, is causing the copper tubes in the heater to degrade and suggested raising pH to 7.6 / 7.8 with goal of a LSI / CSI between -.3 and 0.0, but trying to avoid going over zero which will just worsen the calcium flaking issue.
Also, I do NOT have a bypass system set to bypass the heater. Pool guy suggested it for any time using an AA treatment, although figuring out how to rework the plumbing given the room will be an issue.
This all sounds reasonable, but I wanted your input. My question is if there could be actual copper from the heater tubes flaking off and if a low CSI could be a cause of that. Or, if the CSI isn't the issue and the issue is the lack of a bypass. My goal is to lengthen the life of the pool heater as long as I can as I have to replace the liner at some point due to excessive wrinkling, and I need a new auto cover soon, and and and.
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