Can the SLAM process hurt my pool heater?

[JRzMom]

When we installed the pool heater last year, the instructions required we place the heater before the in-line chlorinator to prevent damage to the heating element. Upon opening our pool this year, we have a tremendous amount of algae, and I need to SLAM it. I'm showing no CYA or FC, although the pH level is perfect (7.6). I haven't used the in-line chlorinator (tablets) since I started using liquid chlorine, but I am concerned that the amount of chlorine during SLAM will damage my heater. I will be using the sock method to deal with the CYA simultaneously. I love my heater and don't want to lose it!

 

[Rocket J Squirrel]

High chlorine won't hurt your heater. It's the acid in the trichlor pucks that can cause damage if it sits in the heater.

 

[ajw22]

What model heater are we discussing?

Add it to your signature.

Your concern is why I recommend a Heater Bypass - Further Reading

 

[JRzMom]

High chlorine won't hurt your heater. It's the acid in the trichlor pucks that can cause damage if it sits in the heater.

Thank you. That makes sense to me. We no longer use the trichlor pucks. We switched to liquid chlorine last year. I'm going to start SLAM tomorrow.

 

[JRzMom]

High chlorine won't hurt your heater. It's the acid in the trichlor pucks that can cause damage if it sits in the heater.

I planned to add CYA using the sock method, but it is probably a good idea to put it in the pool in front of the return jet instead of the skimmer basket, right? I would think it would be too concentrated going through my heater from the skimmer (too close). Also, I notice my heater's element is titanium, not copper. Does that make a difference?

 

[ajw22]

I planned to add CYA using the sock method, but it is probably a good idea to put it in the pool in front of the return jet instead of the skimmer basket, right?

Either one works.

I would think it would be too concentrated going through my heater from the skimmer (too close).

It is not. CYA is a weak acid.

Also, I notice my heater's element is titanium, not copper. Does that make a difference?

No, titanium is less sensitive to chemicals then copper.

 

[nuttyp]

Seems to me that methods to add CYA and other chemicals gets debated over the years in many threads here. The simplest TFP approach I've read makes the most sense in my opinion, which is: "No chemicals added through the skimmer". Following that approach seems to "dissolve" (haha) all the debates & concerns about the type of metal in the heater, the caustic level of CYA as it is added, etc., and especially the impact on the pump and heater over the course of years when adding through the skimmer. My CYA sock is in a floating duck tethered (with wax string) to a pool jet, it's never in the way. Once every month or two I squeeze the sock a few times and add new CYA to it, based on testing of course. CYA may be a "weak" acid, especially when diluted among thousands of gallons of water. But I do have to replace the sock every six months because otherwise it will totally disintegrate - and that makes a mess. So there's that, but maybe I just buy cheap white socks

 

[JRzMom]

Thank you, everyone, for your help. My SLAM seems to be working, as the pool is visibly clearer on day two. I am finally getting proficient in testing, too. I added the CYA sock, but that isn't showing up yet, so I put my winter cover over to keep the sun out (and save me some $$ in chlorine). It seems to help a lot. Only lost 1.5 ppm overnight, too. I scrubbed as best I could from the sides, but the water was too darned cold to get in and scrub better. I'm running my little robot vacuum until I can see the bottom, then I'll use the vacuum through the filter. I did clean out the filter once, but will likely have to do that several times. It is exhausting, but I look forward to inflating my float, turning on the heater, and enjoying my first dip. This forum is the best! And I love the Pool Math app.

 

[JRzMom]

I've been SLAMming for four days now, and the pool is much better but still a bit cloudy. It was clear this morning but cloudy again by afternoon, so I am continuing my SLAM. I was able to get in and scrub everything, including the skimmer and basket. I'll do a filter clean again tomorrow, even if the cloudiness improves. I'll test overnight FC, and fingers crossed, I can use it for the holiday weekend! I also bought new reagents (I already have a new chlorine-testing kit), so I am looking forward to more accurate testing of CYA (and pH/Alk once the SLAM is done). My kit expired in 2022. LOL I'm not losing a lot of chlorine, even on sunny days.
4 Days ago:
FC - 0
CC - 0
pH - 7.6
CYA - 0
Today:
FC - 10 (SLAM level according to the app)
CC - .5
CYA - under 30 (guessing 15 by the cloudiness)
Temp - 74 degrees F

I have the CYA sock and squeeze it once a day, but the CYA only increased a little bit. Again, it may be due to expired reagents. Wish me luck!