Reduce running time on Intex Krystal Clear Saltwater System

Amelsfort

Member
Apr 20, 2021
10
Tilburg, NL
A few years ago I built a small pool in our garden. After a few years of maintaining the chloride by hand, last year I decided to switch to salt water.
I ordered an Intex Krystal Clear saltwater system (the smallest one they have) and installed it. Soon I discovered that my pool is actually a bit too small for this one. I set the device to its minimal settings: run for 1 hour each day. After a few days, I measured the chlorine levels and noticed it was way to high!
The only way to keep the levels right, was to turn the device off and on manually instead of having it run automatically each day. :(

For the upcoming season I am looking for a way to have the system run automatically, but less than one hour a day. Unfortunately, when you cut the power and put it back on, the device starts in standby mode and doesn't start until you press a button. So adding a remote power switch is not an option. Now I have also added an ESP8266 to the pool pump to wifi-enable it, so I was thinking about adding another one to the SWG. Does anyone have any experience with this? I can think of a few options to limit the amount of chlorine:
1. switch the power to the cell
2. limit the current to the cell
3. override the power button so I can remotely (from my home automation system) switch the device off before it would finish its program

I didn't open up the device yet, so without knowing the details I guess option 3 would be the easiest. That way I can let my home automation start and stop the device whenever I want, together with the pump.

Besides all this I was also wondering how the whole process works and how the chlorine levels are maintained. Since the system ran too long/often for my pool, I suppose every time it ran, some amount of salt was converted to chlorine. After running, the chlorine was slowly converted back to salt, but before it was back on its 'original' level, the system started again. This caused the level of chlorine to raise higher every time.
But this would mean the amount of running time would need to be very precise: a bit too long and the levels raise with every run (and lower between the runs, but less than raising). If the running times are too short, the levels would slowly decrease every time as the levels drop more between the runs than they rise during the run.
One way this could work, is when the chlorine level drops to 0 every time. That way the device will generate the same amount of chlorine every time. The other way around is also possible: convert all the salt to chlorine every time. But then I wouldn't have had the high levels, so I suppose this is not the case.

Can someone please explain?
 

jseyfert3

Silver Supporter
Bronze Supporter
TFP Guide
Oct 20, 2017
1,515
Southern WI
Pool Size
15000
Surface
Vinyl
Chlorine
Liquid Chlorine
Welcome to TFP!

How small is your pool? This is the first I’ve ever heard (or imagined) that an Intex SWCG is so big an hour a day of running is too much.

SWCG do not have chlorine feedback by themselves. They are simply time based devices. Larger ones also have power settings. They are used by setting the hours and/or power level (if available) such that the output is roughly the same as the chlorine demand. This is usually able to be balanced fairly well so the settings only have to be adjusted a few times throughout the year as chlorine demand changes naturally as bather load, sunlight, and heat based chlorine loss changes through the year.

In any case I can’t answer your original question, but you could try some searches here as I’ve seen threads where people had the same question on the Intex pumps, as most of those do not restart unless a button is pushed after a power loss and people wanted to be able to control them remotely. I’m unsure if solutions were found or not though.
 

Amelsfort

Member
Apr 20, 2021
10
Tilburg, NL
I just added my signature. :) I have no exact measures (the pool is partly curved, so hard to measure) but I guess it's between 1000 and 1500 liters. Three adults can easily lay down in the pool to relax, but swimming is not an option. With a water depth of 60cm that's never an option though. :)
Next time I fill it, I will measure the exact amount of water.

I did find some threads about automating the SWG indeed, but I didn't find the right solution here yet. Sometimes because the used device had some other options, other times because no solution was found.

Reading your comment about the device not having feedback and having to adjust the settings, I guess my theory about the increasing levels is correct? Since the Intex device can only be set to whole hours of running time (always daily), it's impossible to make small adjustments. So another reason to automate this. :)
 

jseyfert3

Silver Supporter
Bronze Supporter
TFP Guide
Oct 20, 2017
1,515
Southern WI
Pool Size
15000
Surface
Vinyl
Chlorine
Liquid Chlorine
Ah, that makes sense. My hot tub is 425 gallons or 1600 liters. So you essentially have a hot tub sized pool.

If you don’t figure out the control issue for the Intex, there are various hot tub sized SWCGs. I have the Saltron Mini. It’s adjustable in hours per day just like the Intex. However I believe if powered off and powered on it starts a new cycle, making it easy to automate in time per day. These hot tub sized ones also are a lot smaller so they would be easier to adjust the output to match your need. I can check this for you if your interested.

There’s also the Chloromatic? which has some sort of sensing for chlorine but I’m still waiting to hear back how that works long term, it’s also rather expensive.
 

Amelsfort

Member
Apr 20, 2021
10
Tilburg, NL
Yeah, a hot tub is probably a better name than 'pool'. :)
Too bad I haven't checked this last year, but maybe I'll take a look at the hot tub SWG's. Thanks for the tip!