If your Pentair salt system is throwing a “check cell” or low-chlorine alert and the cell is an IntelliChlor IC40, you have a decision to make: replace it with the same thing, or upgrade. We made that call recently on a pool in Benders Landing in Spring, TX, so this is a practical walkthrough of what actually differs, how to tell a cell is done, and what the swap involves.
First: Is the Salt Cell Really the Problem?
A low-chlorine alert doesn’t automatically mean a dead cell. Before anyone quotes you a new one, these need ruling out:
- Salt level. Low salt reads as low output. Test the water independently rather than trusting the controller’s number alone.
- Scale on the plates. Calcium buildup between the blades chokes production. Our area’s hard water makes this common, and a scaled cell can often be cleaned rather than replaced.
- Flow. A dirty filter, full pump basket or closed valve can keep the cell from generating at all.
- Run time. If the pump schedule was cut back, the cell simply isn’t running long enough to keep up with Texas heat.
When all of those check out and output is still down, the cell’s plates are worn out. That’s what we found on the Benders Landing pool: an IC40 around five and a half years old, salt and flow fine, cell no longer producing. At that age, worn plates are expected rather than surprising.
IC40 vs. IntelliChlor Plus40: What Actually Changed
Pentair’s own comparison describes the Plus40 as building on the IC40 “with improved accuracy, diagnostics, durability, and serviceability.” In plain terms, per Pentair:
Two points matter most for a homeowner. Pentair describes the Plus40 as a drop-in replacement for existing Pentair systems, and both models integrate with Pentair automation — so upgrading doesn’t mean re-engineering your equipment pad. The capacity rating is the same, so you’re not trading output for the newer features.
Replace Like-for-Like or Upgrade?
Our recommendation on the Benders Landing job was the upgrade, and the customer approved it. The reasoning is simple: the job is the same labor either way, the Plus40 fits the existing Pentair setup, and the better diagnostics mean the next problem gets flagged more clearly. When a cell only fails every several years, putting in the newer design is the sensible choice. If your quote is for a like-for-like IC40, ask why — there may be a good reason, but it’s worth the question.
The Old IC40
About five and a half years of service before the plates gave out.
The Plus40, Installed
Drop-in on the existing Pentair pad, tested and making chlorine the next day.
What the Swap Involves
On a Pentair pad, a salt cell replacement is a contained job: power down, isolate the cell, remove the old unit, install the new cell, restore power, then verify the system recognizes it and is producing. The step people skip is the last one — confirming salt level and output after the swap, not just that the light came on. You can read exactly how that played out in our Benders Landing salt cell replacement, where the alert came in during a routine week and the new cell was running the following day.
How to Make the Next Cell Last
- Keep salt in the range your system specifies — both too low and too high cause problems.
- Inspect the cell for scale regularly and clean it when needed, rather than waiting for an alert.
- Keep water balanced. High pH and calcium are what drive scaling in the first place.
- Don’t let a clogged filter starve the cell of flow.
That inspection is part of every weekly visit on our saltwater pool service in Spring — which is exactly how the Benders Landing failure was caught early.
Salt system alert in Benders Landing, Spring or The Woodlands? Call or text Steven at (832) 447-4236, or see our Benders Landing pool service page.