Saltwater chlorine generators (SWCGs) are a popular choice among pool owners due to their convenience and steady chlorine output. However, a common issue many encounter is the “Low Salt” warning. This article will help you understand what causes this alert and how to resolve it. Most manufacturers consider a salt level within 400–500 ppm of the actual reading to be acceptable.
Understanding the “Low Salt” Reading
Most saltwater systems don’t have a dedicated salt sensor. Instead, they estimate salt levels using an algorithm based on several factors:
- Water temperature
- Cell amperage
- Cell voltage
Because these systems rely on indirect measurements, the “low salt” message might not always reflect the actual salt level in your pool.
Step-by-Step Troubleshooting
- Test the Salt Level in the Pool Water
- Use a reliable salt test kit or digital meter to measure the actual salt concentration in the water. Most SWCGs operate best within a range of 2,500–3,500 ppm (parts per million). Compare your reading with the manufacturer’s recommended range.
- If your reading is low, then follow the manufacturer’s instructions on how to add salt.
- Inspect the Salt Cell
- Calcium buildup on the cell plates can interfere with proper function and lead to inaccurate salt readings.
- If the cell is dirty, clean it according to the manufacturer’s instructions.
- Check the System’s Settings and Indicators
- Ensure the system is set to the correct cell size.
- Look for any error codes or warning lights that might indicate other issues, such as a need for cleaning.
- Evaluate Water Temperature
- SWCGs often reduce efficiency in cold water, sometimes triggering a “low salt” message.
- If your pool is below 60°F (15°C), consider that temperature might be a factor and consult the manual for cold-weather recommendations.
- Add Salt if Needed
- If your test confirms low salt levels, add pool-grade salt incrementally.
- Allow time for the salt to dissolve and circulate before retesting the levels.
- Reset the System
- After adjustments or cleaning, reset the SWCG to clear any error messages. Consult the manual for the correct reset procedure.
- Calibrate the System (if applicable)
- Some systems allow you to manually calibrate the salt reading. Refer to your system’s manual for guidance.
- If all troubleshooting steps have been followed and the cell is still reading inaccurately, it is time to replace the cell.
Understanding Salt Cell Life
Salt cells are the heart of your SWCG, converting dissolved salt into chlorine. However, they have a finite lifespan, typically lasting 2–7 years depending on usage, maintenance, and water conditions. Signs that your cell might be nearing the end of its life include:
- Persistent “low salt” or “check cell” warnings despite proper salt levels and cleaning.
- Decreased chlorine production.
- Visible wear or damage on the cell plates.
To maximize cell life:
- Clean the cell regularly to prevent calcium buildup.
- Maintain balanced water chemistry, as high calcium hardness or improper pH can accelerate wear.
- Monitor usage, and consider reducing runtime during periods of low pool usage.
- Replace the cell as recommended by the manufacturer to ensure optimal system performance.