How to tell when SWG is not making chlorine


New member
Jun 4, 2013
In-ground pool, about 23,000 gal. system. I can't get FC up to spec. with my t-9 Goldline system. I get zero chlorine with drop test but did get a normal reading at the jet, but should the jet show a high chlorine level when system on superchlorination? My CYA seems on low end. PH about right. Trying to decide if generator is failing. Voltage and amperage is just out of manual stated ranges but probably within tolerance.


LifeTime Supporter
Apr 27, 2013
Central Massachusetts
Here's one way: Turn it off, get your pool "sparkling" by following the shocking process using liquid chlorine and finishing with the overnight FC loss test.

Then the next night turn on pump and your SWCG high enough that it will generate chlorine. Measure the next morning. With no sunlight and no organics consuming chlorine, your FC level should have risen if your SWCG generator is working. You should be able to calculate how many ounces of chlorine were generated even.


TFP Expert
LifeTime Supporter
Jun 5, 2012
DFW, Texas
Welcome to TFP! :wave:

luvbigiron said:
My CYA seems on low end.
:testresults:, including what your CYA level is? Depending on how "low" it is, that could be part of the problem. It is quite possible that your SWG is working fine but that the FC is being consumed by sunlight at a high rate due to a "low" CYA.

It also could be that you have something organic living in the pool that is consuming FC at a high rate. Test results will help us confirm that. Also, how does the water look?

One other thing...Please put the city and state (or country) in which you live in your profile or in your text. Your climate is important to the advice you receive.