How to Troubleshoot a Salt Chlorine Generator

Salt chlorinators, aka salt water pool systems, are very popular these days and rightly so. There is no better or cheaper way to keep your pool sanitized. Modern units have sophisticated circuitry that requires very little oversight and all-in-all are pretty reliable. Most go for years with only an occasional cleaning of the cell. When they quit working however, pool owners often need help in pinpointing the source of the failure and this article was written with that in mind.

If you check your water chemistry on a regular basis, the first sign of a problem might be a sudden absence of chlorine in the water. If your salt system display appears normal, the first thing to check further is the water; have it checked for phosphates and make certain that the cyanuric acid (stabilizer) is up to par. Phosphates are a more common problem than ever before; perhaps because of the unusual weather patterns. If needed, buy the PhosFree treatment and get the reading below 100 PPB.

If you do not check your water chemistry on a regular basis, the first sign of trouble will probably be algae in the shallow areas of the pool. Whether the generator is working or not, you may need to treat the pool immediately with granular shock and algaecide to prevent a full scale algae bloom. It’s always cheaper to attack algae early and aggressively than to wait. In warm weather, it grows quickly.

After eliminating the possibilities described above, it’s time to look more closely at the salt chlorinator system. If the unit is totally dark with no signs of life, check the power source and ensure that it is getting power. Ideally, check the source with a voltmeter. If the proper voltage is going to the unit, check to see if the chlorinator control unit has either a reset button or an internal fuse. These protect the unit against a short in the cell. It only takes a little grass or a ball of hair to lodge momentarily between the titanium plates to trip the reset button or blow the fuse. If the cell is crusted over with calcium and the plates are bridged, this is obviously the problem. Clean the cell, change the fuse, and you should be good to go.

If the control appears to be working normally, it’s time to check to see if the cell is producing chlorine gas. If your unit has a clear cell body, you can simply observe the cell while it’s working and if you see the fog coming off the plates, it is working. If the fog is minimal, the cell could be worn out. Most brands have cells that last about 8,000 hours and a couple brands have cells that are made to last 15,000 hours. Using your history of hours run per day, you can do the math and determine if the cell is just at the end of its life. If you have ever cleaned your cell with too strong an acid solution or if you have ever made the mistake of allowing it to soak for too long, all bets are off and you may be faced with an early cell failure. Get out the old Visa card. Some pool stores have a device that tests a salt cell but many technicians doubt the validity of these machines. (Cell failure = Commission)

If your salt system has an opaque cell body, the only way to test for activity is to capture some water coming out of the jets in the pool and test it for chlorine. Use an empty coke bottle or such, hold your thumb over the opening, and hold it up against the pool return jet. Try not to let the sample get too diluted with water from the rest of the pool. If your system is performing, you should see a difference in the chlorine level in this sample vs. a reading taken in the far corner of the pool.

In some cases, salt systems are performing as they should but the display is giving erroneous readings for salinity and/or temperature. Usually, this is a sign that the calibration circuitry has been compromised by a power surge. Many units can be recalibrated on site by the homeowner. Check your owner’s manual or check Google for calibration instructions for your model. If your display or warning lights indicate “water fault” or “water flow” problems, check to see that the water is flowing freely through the generator cell. If the water is flowing, you may have a bad flow switch. Most units have a separate flow switch but some have this function built into the cell. On some, the water fault indication can occur if the calibration mentioned above is drastically off. In all cases, closely examine the electrical connections between the cell and the control and between the flow switch (if present) and the control. These connections must be clean, tight, and dry. Often, a little sandpaper on these terminals can bring a dead system back to life.

Even if you are unable to get your generator working, going through these steps will prepare you for a phone call to the factory techs. Most manufacturers expect their installers to handle the problems but if you try you can usually speak to one of their techs and get their help. Like everything else, salt chlorinators are not really complicated once you understand how they work.

Thanks for reading and happy swimming!