Sometimes there are instances where it seems like the salt cell is not producing chlroine. If all the appropriate lights are solid green on the salt cell and your chlorine is constantly 0, it might not be working properly. One thing you should check first is your Cya level. Cya is like sunscreen for chlorine so if the level is too low, your chlorine will get eaten up by the sun very quickly. If thats in check, here are some ways to test the cell.
Easy Method:
Turn the salt cell up to 100% and let it run for a couple of minutes. Then, test the water in two different places in the pool; one right outside the return jets and one in a spot away from the returns. The chlorine level right outside the return jets should be much more concentrated than the other one. If this is not the case, you should do a bucket test to confirm the cell is not working.
Bucket Test Method:
Doing a bucket test will obviously show you if the cell is producing chlorine or not. First, confirm that the salinity level of the pool water is in range (2800ppm-4500ppm). Next, get a 5 gallon bucket and fill it with pool water. Turn the salt cell up to 100% and disconnect the unions from the salt cell. With the salt cell still plugged in, submerse the cell in the water. Remove the grate on the side of the cell with the flow switch. With the cell compltely under water, press and hold the flow switch forward until it hits its connection point. Continute to hold the flow switch down. You'll see the lights on the cell cycle while its testing the water and then they will show the results. If the salt, cell, and flow lights are all solid green and the output it set to 100%, you should start seeing chlorine being produced. White foam will start to sizzle from the cell. If there isn't anything happening the cell is defective.
The flow switch tests the water salinity, flow, and temperature. If you're holding down the flow switch and the flow light stays red, the switch needs to be replaced. If you've confirmed that the salt level is accurate and it is saying low salt, the switch needs to be replaced. Lastly, if the cell light is blinking it either needs to be cleaned or the cell is bad (read our article about cleaning your salt cell to learn more about that).