How do you know if the salt cell is working?

[Mathisc1]

My ORP is dropping, chlorine level is low. How can this be checked?

 

[needsajet]

Welcome to TFP. Good to have you here

There should be small bubbles coming out of the return (definitely the nearest return, if not all).

When bubbles are coming out of the return, push a water sample bottle down into the water neck down. Put the neck of a water sample bottle over a return jet, then tip it downwards so the air can get out and water from the return goes in. Test that sample for FC and see if it's higher than the pool.

 

[Jimrahbe]

Another way, is to check the FC level after the sun goes down and then check it again before the sun comes up. Of course this requires the SWG to be running all night. If you get a big increase in chlorine level overnight, it's working. If no increase then run the same overnight test again, with the SWG off. If the overnight FC loss is less than 1 ppm, then you can be pretty sure the SWG is not working. Obviously, it the overnight FC loss is greater than 1 ppm, you've got something growing in your pool.

What FC level do you normally try to maintain?

Are you using your automation to tell you what your FC level is? It could be a bad ORP probe. What are you using to manually test your chemicals? How about providing your current reading:

FC
CC
pH
TA
CH
CYA

Thanks,

Jim R.

 

[pooldv]

Most often when people think their SWG is no longer making chlorine it is in reality algae consuming the chlorine faster than the cell can produce it. Try doing an Overnight Chlorine Loss Test to see if there is organic matter consuming the cholorine. Or run the SWG all night to see if FC goes up as Jim suggested. Most SWG cells will give a cell error light if there is an issue with the cell producing chlorine.

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