Intellichlor IC20, no free chlorine

[TelMinz]

I take care of a 5000gal gunite pool that has a pentair easytouch system with an Intellichlor IC20 SWG. The easytouch controls the cell. The transformer and daughter board are inside the easytouch box. For several weeks now there has been no chlorine when I test the water. I keep the CYA levels between 60-70. All other parameters are kept where they should be, and I service all my pools twice a week. I first cleaned the salt cell according to the directions for the IC20, I even bought one of those stands to hold it. I checked the transformer, it’s outputting 30vac, which is in line with what specs I could find online of 22~39vac, so in the middle. The daughter board is outputting 38vdc. When the cell light is on it draws about 3amps. So I came to the conclusion the cell maybe stopped working, it was at 80% life, but the plates inside were corroded badly. When I took over this pool it was completely blocked and scaled up, so it wasn’t too hard to believe that the abuse it had seen just caused an early death. It even had a burnt out led on the output level indicator.

But now I’ve put on a brand new cell, and still no chlorine. The lights on the cell light up like they should, but even when I test the water from the output jet there is no chlorine. I’m out of ideas on what could be the problem. If anyone has any suggestions I’d sure appreciate it.

Test from today - Ph 7.5, Chlorine 0, Alkalinity 90, Salt 3650ppm, Cya 70, Calcium Hardness 180, TDS 5320

I’m using a Taylor test kit and and electronic tester for the salt and tds. I don’t normally check tds, but thought it might be useful to know. I have several pools that I maintain, this is the only one that I have this problem with.

 

[Jimrahbe]

T,

The IntelliChor either works or it does not. With the output set to 50% the Cell light should be on for 2.5 minutes and then off for 2.5 minutes.

If the cell light is working than the cell should be making chlorine.

Algae will consume all the chlorine that the cell can make.

As a test you should add enough Liquid Chlorine to bring the FC up to about 5 ppm and see if it stays there or if it is quickly consumed.

What is the cell's output %?? Is it flashing??

How long does the pump run per day?

Thanks,

Jim R.

 

[TelMinz]

T,

The IntelliChor either works or it does not. With the output set to 50% the Cell light should be on for 2.5 minutes and then off for 2.5 minutes.

If the cell light is working than the cell should be making chlorine.

Algae will consume all the chlorine that the cell can make.

As a test you should add enough Liquid Chlorine to bring the FC up to about 5 ppm and see if it stays there or if it is quickly consumed.

What is the cell's output %?? Is it flashing??

How long does the pump run per day?

Thanks,

Jim R.

I have been treating with liquid chlorine, adding 64oz twice a week. The water stays clear with no algae. When I come to service there is zero chlorine.

The cell is set to 100% in the easytouch and all lights are on solid. The cell light comes on as well.

I have the pump set to run 24hrs a day seven days a week now. I changed it to that over a week ago hoping it would start showing chlorine.

Thank you

 

[wireform]

So this time add the 5ppm chlorine and wait 15 minutes and check again and again until it holds chlorine then you'll need to slam assuming it's the algae problem.

 

[TelMinz]

So this time add the 5ppm chlorine and wait 15 minutes and check again and again until it holds chlorine then you'll need to slam assuming it's the algae problem.

64oz is enough to raise Cl to 10ppm. The water is clear with no algae.

 

[TelMinz]

I guess I should add that I’ve been maintaining this pool for over a year now. This has only become an issue in the last couple months.

 

[TelMinz]

I went back today and checked the chlorine. I added 64oz of liquid chlorine yesterday, it’s back to zero today. The water is crystal clear, but you guys keep talking about algae. If there was algae, wouldn’t the water be cloudy and/or green? Or is it possible to have algae but still have clear water? I also read somewhere that having metals in the pool could cause the chlorine to read zero, and I don’t have a way to test for those. So should I consider draining and refilling? The pool is above ground so draining it would not be an issue.

 

[Jimrahbe]

T,

By the time you see green it is way too late. You can have algae and the water can be clear.

I have not heard of any metals that can consume your chlorine.

Two things can consume chlorine in pools. Sunlight and algae.

How big is your pool in gallons? For small pools it often makes more sense to just drain the water and start over.

Another option is to run what we can the Overnight Chlorine Loss Test or OCLT. This is how. Overnight Chlorine Loss Test

The idea being that at night you can't blame the sunlight for eating the chlorine. So, if you added 10ppm worth of chlorine just after dark, and then tested before sunrise, it should still be there... unless something (algae) consumed it.

Thanks,

Jim R.

 

[TelMinz]

T,

By the time you see green it is way too late. You can have algae and the water can be clear.

I have not heard of any metals that can consume your chlorine.

Two things can consume chlorine in pools. Sunlight and algae.

How big is your pool in gallons? For small pools it often makes more sense to just drain the water and start over.

Another option is to run what we can the Overnight Chlorine Loss Test or OCLT. This is how. Overnight Chlorine Loss Test

The idea being that at night you can't blame the sunlight for eating the chlorine. So, if you added 10ppm worth of chlorine just after dark, and then tested before sunrise, it should still be there... unless something (algae) consumed it.

Thanks,

Jim R.

The pool is 5000 gallons. This is not my personal pool. I can’t come at night, and I also live 1.5hours away from its location.

 

[Jimrahbe]

T,

Then to me it makes sense to just dump the water and start over.

Thanks,

Jim R.

 

[TelMinz]

Just wanted to give an update. I drained the pool and refilled it, I also changed the sand in the sand filter. I think the sand in the filter might of been what caused the issue in the first place. The filter always ran unusually high pressure, 30psi even after backwashing. When I started maintaining this pool a year ago they said that was the normal pressure for it. The pool is only a few years old. All the other pools I maintain run between 6 to 20psi. So when I started vacuuming the sand out, I found sand inside that had turned into bricks. I had to chisel it to break it up to get it out of the filter. There were several very large chunks that had bricked up like that, probably 30-50lbs of sand out of the 350lbs the filter holds. So after a couple hours I was able to get it all out and refill the filter, and it now runs 22psi. The water is crystal clear and has had chlorine both times that I've been back since changing the sand and draining then refilling.