How to Check a Salt Cell Error Light

Check Cell / Clean Cell / Cell Maintenance Indicator

When a “Cell” error light (by any of these names) is illuminated, it is typically going to mean that your system detects a need for the cell to be cleaned. For a few popular models, if the light is flashing instead of solid, it instead is providing a time-based reminder that it is likely to need cleaning. And to complete your troubleshooting, we’ll also go over a handful of other issues which could cause this light to turn on.

Is The Cell Light Solid or Flashing?

A steadily glowing Cell light is the standard way that your salt chlorine generator (SCG) alerts you that the salt cell needs to be cleaned. The determination is based on patterns or trends in cell voltage and cell current.

On the other hand, a flashing light - as found on models such as Hayward AquaRites (and other similar models such as Swimpure Plus, Blue Essence, and more) - is a time-based alert that warns you after a certain number of operating hours.

With one of these models, if your Cell light is flashing, you should take the opportunity to inspect the cell. If you see calcium scale or debris, it is a good time to proactively clean the cell. But regardless of how clean you get your cell, these lights will continue to flash until they are reset - their intent is simply a reminder for you to take a look inside the cell. For most of these models, simply press and hold the diagnostic/status button until the light goes out when you release the button.

Isn’t This Cell Supposed To Be Self-Cleaning?

These days, the majority of SCGs utilize a “self-cleaning” protocol that periodically reverses polarity. The cell blades, or plates, in an SCG function as electrodes and when the system reverses polarity, those that were acting as “anodes” become “cathodes” and vice versa. When this happens, some of the developing deposits or “scale” will loosen from what had been a cathode up until that point.

The important takeaway from this, is that the self-cleaning process doesn’t prevent scale from ever occurring, but rather helps to inhibit its buildup. Without this technology, many salt chlorinators would need to be cleaned as much as weekly or more. But for most pools, it effectively only slows the buildup of deposits on the electrodes, allowing cell cleanings to be measured in months. While some pools in areas where scaling is not prevalent might rarely see an accumulation of calcium buildup, the bottom line is that most pool should still expect that periodic cell cleaning will still be required.

How Frequently Should a Cell Light Occur?

Just how often a cell needs to be cleaned varies widely from pool to pool and can also vary markedly on any single pool over time. Having said that, once every several months is a common figure, but if the light reoccurs in a matter of weeks or even days, then you should test your water chemistry. If the Cell light comes on and the cell needs to be cleaned (after which the warning light goes away), this is a red flag that you need to check your water chemistry’s “balance.”

The common assumption by pool owners is that pool water which tests entirely “in range” must also be “balanced.” However, the specific balance which determines how much scaling might occur in the water is measured by the the Saturation Index - also known as the Langolier Saturation Index (LSI), and more recently as the Calcium Saturation Index (CSI).

The wrong combination of “in-range” water values can cause a Saturation Index that is corrosive at one end of the spectrum, or at the other end of the spectrum the water will be scale-forming and lead to a rapid buildup of deposits and scale on pool and equipment surfaces. Pool water at this end of the spectrum can cause the Cell Light to come on frequently - a high Saturation Index can mean that salt cells might need acid washing in even a matter of a few days.

Some pool stores will calculate this for you when they test water, but if not, you can calculate it based on your test results. An LSI number between -0.2 and 0.2 is considered balanced, but over 0.2 you will experience increasingly rapid buildup of deposits on the salt cell triggering the red light far sooner than expected.

Happily, an LSI calculator is the perfect tool for bringing the water back into balance. By adjusting the inputs and seeing the calculated change in the index, you can determine what changes will bring the water back into balance and protect your pool and pool equipment.

Additional Troubleshooting - If you get a Cell light after thorough cell cleanings.

While the main purpose of a Cell Light is to indicate when a cell might need to be cleaned, it is possible for other factors to also trigger this warning. As mentioned, a SCG usually illuminates this light when there is increased difficulty sending power through the cell. These troubleshooting steps will help you identify if there are other issues (one or more) which might be causing this light.

If you have thoroughly cleaned your cell (multiple times in a row if necessary, until when you clean it with freshly mixed solution you no longer immediately see any “fizzing”, and have flushed it out each time so there are no possible remaining solids inside), then check for these additional factors:

1. Ensure that your pool’s salinity level is not too low. Low salinity makes it harder to pass power through the cell. Independently test your pool’s salt level and ensure that it is well above the minimum level specified for your model SCG.


2. Check the Cell Type or Cell Version (if applicable for your brand and model). For systems with controllers that allow the setting to be changed for the cell capacity, an incorrect setting will cause the system to wrongly calculate the salinity level. If it thinks the salinity is very low, it may also trigger the “Cell” warning.


3. Air collecting in the salt cell. If you have a transparent cell housing, look for an air pocket inside the cell.



If you see air in the cell, or have an opaque cell, you can raise your pump speed to its maximum setting and observe whether the air can be moved through the cell and whether the warning goes away (some models may need to be turned off/on once the flow is higher in order to clear the error and cause them to re-check their diagnostics).

Additionally, one common style salt cell, when installed horizontally, can help prevent an air pocket inside and stay flooded with water more easily simply by rotating the cell.

IMPORTANT: only install horizontally if manufacturer instructions allow this)



Air accumulating in the cell can be an indication that waterflow is too low or that you have a suction-side leak introducing air into the plumbing.

Check the water level in the skimmer and inspect all fittings and connections between the pool and pump.

4. Cold water temperatures can also make it more difficult to pass power through the cell. If your water is cold and approaches the 50’s F or lower, it's very possible this can be at play. Older salt chlorinators or models without a built-in temperature probe can be more prone to this.


5. Take the opportunity to inspect any cell cable connections to ensure they are clean, tight, and free of damage. It is possible for a poor connection to make it too hard to pass power through the Cell. Older salt chlorinators or models which work internally on lower voltages can be more prone to this.


6. If all of your other troubleshooting checks out, and also if your cell is old and has received substantial use over the years, then the cell itself is nearing the end of its lifespan.

If we haven’t led you to and solved your issues, then we advise you to call us at (866) 766-5243 Mon-Thu: 9-4:30 or Fri: 9-3PM Central and a member of our support team will assist you further. Alternatively, you can request assistance online and you will be contacted by a support team member.