Calcium hardness& heat pump

zeke · May 31, 2018

Hi, I have a vinyl liner & understand ch is no too important. Was concerned about low ch possibly being corrosive to heat pump. I have no problem with water quality. I have tft test kit. Cl is a little high now due to shock from opening pool.these my test results for reference
Fc 8
Ph7.4
Ta 80
Ch100
Salt 3500 (a little high)
Thanks for any advice

pooldv · May 31, 2018

The only number that is important as far as heater corrosion goes is pH. Keep pH above 7.0 to avoid heater corrosion.

zeke · May 31, 2018

Thanks very much!

Steve Bee · May 31, 2018

What about salt cells, does low CH damage them?

pooldv · May 31, 2018

Nope.

borjis · May 31, 2018

The one thing it might be useful for (in vinyl lined pools), is as an anti-foaming agent.

I've only seen that happen when CH is around or lower than 60 ppm.

Steve Bee · Jun 4, 2018

my CH was definitely lower than 60, but I dosed it with the recommended amount of calcium chloride to get to 150 ppm, will be testing again tonight. I did notice a bit of what looked like foaming when I pulled the cover off, but that looked more like are bubbles than foam as it would dissipate as soon as the cover was off. My heater recommends a minimum of 150ppm, so I am going to try to keep it at that to avoid any warranty issues.