The saltwater chlorine generator (aka chlorinator or salt generator) in your pool is designed to supply the needed chlorine to sanitize the pool water. If the chlorine generator isn’t producing chlorine or isn’t producing enough chlorine, then something is wrong.
Today, we are going to discuss 13 common reasons your saltwater chlorine generator (SWG) isn’t generating chlorine and how to fix each problem. So let’s dig in.
Here are a few signs that will tell you when the saltwater generator isn’t generating chlorine or not generating enough:
How To Know When Chlorine Generator Isn’t Working
- Low chlorine level in the water (after testing)
- Dirty or murky pool water
- Cloudy pool water
- Error codes on the chlorinator’s display screen
When the generator or salt cell stops working, there will be low chlorine in the water which can lead to bacteria growth, murky pool water and algae bloom. Your chlorine generator should also begin to display error codes.
So now that you know how to spot the fault, why did it happen? Here are 13 reasons your chlorinator isn’t working.
13 Reasons Salt Chlorine Generator Isn’t Working
1) Dirty or Clogged Salt Cell
Dirty here doesn’t mean dirt or dust. Each time your chlorinator runs and discharges chlorine into the pool, it leaves behind calcium deposits.
These deposits can clog up the chlorinator cell over time, decreasing the chlorine output. As a result, you’ll notice a low chlorine reading in the pool water.
How To Fix A Dirty or Clogged Salt Cell
The best way to fix this is to clean the salt cell. Here is a quick rundown of how to do that:
- Test the pool water chemistry to know the chemical levels of the pool water
- Turn off the pool pump and chlorinator
- Remove the salt cell from its housing and spray it with warm water.
- Soak the salt cell in salt cell cleaner for 15 minutes. Distilled white vinegar or muriatic acid (diluted) also works.
- Rinse the chlorinator with a hose and return it
- Adjust the water chemistry to the required levels
- Run the chlorinator and retest the water after a day (you should notice the chlorine has increased.
If your salt cell constantly clogs up, we have an article on this:
Saltwater Chlorinator Cell Constantly Clogs Up (Solved!)
2) Low Salt In The Pool
Your pool chlorine generates chlorine through a process called electrolysis. The salt cell passes an electric current through the salt water to effect a chemical change that turns the salt particles into sodium hypochlorite or hypochlorous acid (i.e. converts the salt to chlorine) that is used to sanitize the pool water.
A low salt level means less chlorine will be generated. If the salt level is low, the generator should indicate a low salt level on the display screen. You can also test the pool salt levels to be certain.
How To Fix A Low Salt Level
The only way to fix this is to add salt to the pool. Here is a quick guide on how to do that:
- Find out how much salt the chlorinator needs. You can find this information on the chlorinator’s user’s manual. Most pools require 3000-4000 ppm of salt.
- Test the salt level using a test kit.
- Calculate how much salt is needed by deducting the current salt level from the required salt level.
- Measure and add the needed salt to the pool. Let the pump run for 3-6 hours.
- Test and adjust the water chemistry if necessary.
- High purity salt for saltwater chlorine systems
- Dissolves quickly when distributed over a large water surface
- For pools & spas
3) Salt Water Generator Control Unit Not Working
The control panel of the chlorinator is used to control every feature and action of the salt cell. If the chlorinator panel is damaged or not working, then the salt cell will not work.
How To Fix the Control Panel
In most cases, the chlorine generator control panel is not serviceable. However, before you decide to replace it, there are a few simple things you can check.
- Has the circuit breaker tripped?
- Is there power to the unit? (if the circuit breaker hasn’t tripped, there could be a fault with the wiring to the chlorinator)
You can do this yourself or hire an electrician.
4) Salt Cell Needs Replacing
The lifespan of saltwater cells isn’t usually long. At best, a salt cell will last about 5 years before it wears out. So if yours has lasted that long, then you might need a replacement.
You can purchase a new salt cell from here.
- Fixes low chlorine output
- Fixes warning light issues
- Suits a wide range of saltwater chlorine generators
Usually, when this happens, the display screen of the saltwater system will show error messages even when the salt in the pool is at the ideal level.
Before you rush out and replace the salt cell though, go through this entire list looking for other faults.
How To Replace A Salt Cell
Here is a quick rundown of how to replace a salt cell:
- Turn off the pool pump and saltwater generator
- Use a wrench to loosen the screws
- Take off the o-rings and washer
- Wipe and clean the cell housing
- Return the o-rings correctly in place
- Fix the new salt cell to the plumbing lines
- Connect the salt cell to the control box. A user’s manual will come in handy here.
- Check the pool salinity levels (add salt if needed) and test run the chlorinator to be sure it’s working.
5) Faulty Test Kit
Test kits range in quality and often cheap ones aren’t accurate. This is particularly true for test strips. In addition to test, most test kits have an expiry date and if the kit or strips are used after the expiry date has passed, the test may not work or be inaccurate.
If you test for salt levels in your pool with faulty test strips, you are sure to get an inaccurate chlorine reading which can make you think that the chlorinator is malfunctioning.
As an expert tip, always check the expiration date on your test strips before using them.
- Tests total alkalinity, free/combined chlorine, cyanuric acid, calcium hardness & pH
- Extremely accurate (better than test strips)
- For pools & spas
6) Power Output Is Set Too Low
If the chlorine generator isn’t set high enough, it will not generate enough chlorine to keep up with the pool’s demand. The power level you set your chlorinator too will depend on the size of the chlorinator, the amount of time you run the chlorinator for, the pool size and your pool.
Many pools are able to run for 8-10 hours a day at 50-60% power level and produce adequate amounts of chlorine.
How to Adjust Chlorine Generator Power Level
There’s no one perfect setting. It’s a matter of trial and error. On the generator control panel, start with 50% power and run your chlorinator for 10 hours. Then test the pool’s chlorine levels. If the chlorine is still low or hasn’t increased, try increasing the power to 70%. If the chlorine level is too high, back off the power. Keep adjusting and testing until you have a stable chlorine level (which should be 3-5 ppm).
7) Algae Using Up Chlorine
There may not actually be anything wrong with your salt cell or chlorinator.
If you notice green, black, or dark blue patches in and around your pool walls, it’s likely an algae bloom. When you have algae bloom in the pool, the chlorine levels will be rapidly depleted.
When this happens, you get a low chlorine reading in the pool and the water will start to stink and turn greenish.
How To Fix An Algae Problem
The best way to fix this is to shock the pool and maintain a shock level of chlorine until you have killed off all the algae. For full details, check out our article here: Green Pool – Guide to Easily Preventing & Removing Pool Algae
8) Low Water Flow
If your chlorine generator cell isn’t getting enough water, then either the chlorine generator will stop working completely or you may have reduced chlorine output. Saltwater generators are designed with flow sensors to monitor the water flow into the salt cell.
In some cases, if there will be a warning light on the saltwater generator (chlorinator), but this is usually only if there isn’t any water movement.
How to Fix Low Water Flow
If you have a variable flow pool pump, it’s quite possible that the speed (measured in RPM, also gallons per minute – GPM) is set too low. Try increasing the speed of the pump a little.
You could also have another issue with the pool’s circulation. Check the flow of water coming out of the return jets. Is it normal or does it feel weak? If it’s weak it could be a number of reasons including blockages, low pool water level, or a dirty filter.
9) Faulty Temperature Sensor
The temperature sensor monitors the pool water temperature and turns off the chlorine generator when the water temperature gets too cold or too hot. And if the temperature sensor is faulty, it may falsely shut the chlorinator off.
How To Fix A Faulty Temperature Sensor
In some cases, there is an external sensor that is fitted into the pipes, usually near the salt cell. The first thing to check is that the plug to the sensor is on tight. If it is on tight, then you could try replacing the sensor and see if this fixes the issue.
In other models, the sensor is designed inside the salt cell so you can’t replace or repair it without replacing the entire salt cell.
10) Water Temperature Is Too Low
When the water temperature is too low, the temperature sensor will shut off the generator to prevent freeze damage. For many salt systems, when the pool water is below about 59°F (15°C) they will stop working. But it does vary from model to model.
We have a full list of the temperatures saltwater chlorine generators stop working here:
Lowest Temperatures Salt Water Generator Cells Work At
How To Fix A Low Water Temperature
You can do this by running the pool pump for extended hours. As the water molecules rub against each other, heat is created to warm up the pool water. You can also install a pool heater.
11) Faulty Flow Sensor or Switch
The flow sensor monitors how much water flows into the salt cell. If there isn’t enough water flow, the sensor will shut off the chlorine generator.
But If the flow sensor is faulty, it will pick the wrong flow reading and can shut off the chlorinator even when there is proper water flow.
How To Fix a Faulty Flow Sensor
Before you replace the flow sensor, make sure it is plugged in properly. The plug should be tight. The flow sensor is usually located in the pipe near the salt cell.
To replace the flow sensor:
- Turn off power at the circuit breaker and turn off the pool pump
- Locate and unplug the flow switch cable that connects to the chlorinator’s control box
- Turn (counterclockwise) and remove the flow switch
- Inspect the flow switch for damaged or stuck debris
- Wrap plumber’s tape around the new flow switch so it’s sealed tight
- Fix the new flow switch in place and turn (clockwise)
- Plug the flow switch cable into the chlorinator’s control box.
- Turn on the pool pump and power to test run the chlorinator.
12) Loose Salt Cell Plugs
The salt cell has a control box where all the cords are fixed. There is also a plug that connects onto the salt cell. If any of these plugs is loose, it can cause saltwater system malfunction.
How To Fix Loose Salt Cell Plugs
- Turn off power at the circuit breaker
- Open the control box and inspect all cords and plugs
- Push the plugs in and check they are tightly fitted
- Close the control box and turn on power
- Inspect the salt chlorinator.
13) Unplugged Unit or Tripped Power
First, let’s make sure it’s not something silly like someone accidentally unplugging the saltwater chlorine generator control panel.
If the unit is plugged in, check if the circuit breaker has tripped. If it has, reset it. And if it immediately trips or trips again later, then there is a problem with the control unit or the wiring. You’ll need an electrician to sort this.
Overall, saltwater generators are great devices, but they are also prone to different faults. However, the guide above will help you fix any problem you may encounter.
So there you have it. If you liked this post, ensure to check out others like it on this website for professional pool tips.