What's the real deal with Calcium Hardness and Pool Heaters?

[Tomolena]

Yesterday, I came home from the pool store with 25 pounds of CH raiser that the saleslady convinced me I absolutely needed to protect my pool heater from damage. I had just emptied and re-filled my pool and my CH is currently 30ppm. When I read thru this forum, a number of posters tell us it's all a scam and low CH has no effect on your heat exchanger. Yet, most pool related websites, and every pool store guy I ever spoke to says the opposite. Even the manual for my heater indicates I need to keep my CH within a certain range.

I place a lot of stock in the information I get from the people in this forum, but I'm a little confused by the opposing points of view on this. So what's the consensus here on this issue?

 

[borjis]

As it applies to vinyl liner pools only, If you don't follow the owners manual, that the heater mfg might find a way to not honor the warranty,
say if a factory trained tech came in to work on it and tested your chemical levels. I've never heard of it happening but
that's the way of thinking on that.

As far as I know there is no way possible that a lack of CH would harm a copper heat exchanger.
off PH or freezing damage would do far more harm to it.

They also say in the manual about not exceeding 2ppm in chlorine. ever.
The theory is they just use boilerplate terminology of historical pool care scenarios for that.

So if your CYA is 50 (like I run mine each season) and I have my nominal FC of 6ppm, does that
void my warranty too?

I've been debating wether or not to ever add CH again, seems like I'd lose that scenario regardless.

Maybe one of our resident heater experts, Paul can chime in. I'd be very interested to hear his professional opinion.

 

[Patrick_B]

The truth is that corrosion from low CH levels does not apply to metallurgy. It applies to plaster type materials. What should concern you with pool heater corrosion is low pH, and or High Chlorine.

Low Calcium related metal corrosion is outdated and misunderstood information.

And let me add something. In the water treatment industry, certain systems have their internal metallic surfaces protected by the controlled application of a very thin layer of Calcium combined with Phosphates. This is done carefully, under tight controls while the systems are on line and running. It can be a delicate manuver to get this just right and not over do it.

It is partially (I think) where the "understanding" and misnomers come from regarding Calcium protecting metals.

 

[ps0303]

Yesterday, I came home from the pool store with 25 pounds of CH raiser that the saleslady convinced me I absolutely needed to protect my pool heater from damage. I had just emptied and re-filled my pool and my CH is currently 30ppm. When I read thru this forum, a number of posters tell us it's all a scam and low CH has no effect on your heat exchanger. Yet, most pool related websites, and every pool store guy I ever spoke to says the opposite. Even the manual for my heater indicates I need to keep my CH within a certain range.

I place a lot of stock in the information I get from the people in this forum, but I'm a little confused by the opposing points of view on this. So what's the consensus here on this issue?

Don't go back to that pool store. They do not have any clue what they are doing based upon what she told you.

CH is only for the finish on your pool if you have that type of pool.

Yes you do need to keep CH in range but it will not have an affect on the heat exchanger. Pay attention to all of your water chemistry and with a gas heater make sure your PH is always in range.

 

[Tomolena]

There are three types of pool store people; honest people, dishonest people, and people who honestly don't know what they're talking about. I believe this woman fell into that third category. It seems there is a lot of disinformation in the industry and it's not helped by the chemistry specs that the heater manufacturers are putting in their warranties. I have this 25lb bucket so I'm going to push my CH up into the "accepted" range and not worry about it for the rest of the season.

 

[YippeeSkippy]

I have this 25lb bucket so I'm going to push my CH up into the "accepted" range and not worry about it for the rest of the season.

Sounds like a plan!

Yippee