Testing Salt Water Chlorine Generators

[Mike_W]

There are always many questions on the forum about cell failure, or cells that are under performing. Over my time on TFP, I have seen threads that suggest taking a suspect SWG cell to a pool store (Leslies, et al) to "get it tested". Can someone enlighten me on what they actually test at the stores? Do they somehow measure the actual chlorine generation capability of the cell or is it a check for scaling then an operating voltage/current test, or something else? Seems to me that a test that creates chlorine in a store environment might be hard to do.

My fairly new AquaRite T-15 cell seems to generate less chlorine than the old one did. Time permitting, I hope to run my cell for a couple of hours at night this weekend with my system set to spa mode and measure the amount of chlorine generated. If my calculations are correct, it should increase the free chlorine in my ~500 gal spa by about 14.5 ppm/hour. The pool is in good shape with less than .5 ppm CC. Air and water temps are in the high 60's to low 70's. Flow switch is before the pool/spa return valve. My AquaRite control box is an older model and is T-15 only.

Does this seem like a reasonable approach?

Thanks,
Mike

 

[pooladdict]

If the store has a tester they can test it, its rare for most stores to have one though. You can go through diagnostics to see if everything is ok.

 

[ping]

I believe most of the Leslies pool stores near us have testers for the AquaRite cells. The test unit somehow determines if the cell is working or not. I think the test is more like a working or not working type of test.

Your idea of running the spa for an hour should give you a good estimate of how much chlorine is being generated. Make sure you run the SWG at 100% and don't run the heater. Your FC increase calculation is accurate for the T-15 cell.

 

[malcolmb5325]

they are testing to see what amperage the cell is drawing when placed in a bucket of salt water at recommended levels, normally at 4000ppm (@ 24° C water temp) when connected to a power pack. a brand new cell will draw a determined amperage (should be listed on your power pack) and as it starts to die the current draw reduces as the plates wear away.

 

[JoshU]

I believe most of the Leslies pool stores near us have testers for the AquaRite cells. The test unit somehow determines if the cell is working or not. I think the test is more like a working or not working type of test.

Correct, the Hayward unit does a total "pass" or "fail" test.

No other manufacturers that I know of offer a test unit like Hayward does. AutoPilot for example has on board diagnostics which tests not only the cell but also the power module board inside of the unit.