Check Salt Cell
Pentair Salt Chlorinator
Severity: ModerateWhat Does This Error Mean?
The Pentair Check Salt Cell warning means the control board has detected a problem with the electrolytic cell — either the cell is coated with calcium scale, the salt level is incorrect, or the cell is reaching end of life. Calcium scale on the cell plates is the most common cause.
Affected Models
- Pentair IntelliChlor IC40
- Pentair IntelliChlor IC20
- Pentair IntelliChlor IC15
- Pentair IntelliChlor IC60
Common Causes
- Calcium scale buildup on the cell plates — most common cause
- Salt level outside the ideal range (2700-3400 PPM for most IntelliChlor models)
- Cell reaching end of service life (typically 3-7 years)
- Flow rate too low — cell requires minimum flow to operate
- Cell connector or cable fault preventing communication with the control board
How to Fix It
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Test the pool salt level with an accurate test kit or digital meter.
The IntelliChlor operates best between 2700-3400 PPM. Strip tests are not accurate enough for salt — use a digital salinity meter or take a water sample to your pool store. Adjust salt if needed and recheck after running the pump for 24 hours.
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Inspect the cell for white or grey calcium scale on the plates.
Remove the cell from the plumbing fittings and hold it up to a light. White crusty deposits on the titanium plates confirm scale buildup — this is the most common cause of Check Salt Cell on hard water pools.
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Clean the cell with an acid wash solution.
Mix 1 part muriatic acid with 10 parts water (always add acid to water, never the reverse). Stand the cell upright with one end capped (use the cleaning stand if you have one) and pour the solution inside. Allow to soak for 5-10 minutes — you will see fizzing as scale dissolves. Rinse thoroughly with a garden hose. Do not soak for longer than 15 minutes or repeatedly acid-wash — it shortens cell life.
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Reinstall the cell and reset the fault on the controller.
Reconnect the cell and power on the IntelliChlor controller. On most models, the Check Cell light will clear automatically once the issue is resolved. Run a full pump cycle and verify the cell is producing chlorine (check free chlorine level after 24 hours).
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Consider cell replacement if cleaning does not resolve the warning.
IntelliChlor cells have a rated lifespan of 3-7 years depending on usage and water chemistry. If the cell is old, has been cleaned multiple times, and still shows the warning, the plates may be worn beyond recovery. A replacement cell will clear the fault immediately.
Frequently Asked Questions
How often should I clean my Pentair IntelliChlor cell?
Pentair recommends inspecting the cell every 3 months and cleaning only when scale is visible. Over-cleaning with acid shortens cell life. In hard-water areas (high calcium hardness above 400 PPM), scale forms faster — every 2-3 months of cleaning may be necessary. Keeping calcium hardness between 200-400 PPM and pH between 7.4-7.6 significantly slows scale formation.
My Pentair cell was just installed — why is Check Salt Cell already showing?
On a brand-new cell, the most common cause is incorrect salt level. New pools and pools after a water change often need salt added — verify the level is 2700-3400 PPM. Also check the flow rate — the cell will not work and may fault if water flow is too low.