Cleaning fixes scale. It does not fix worn plates.
Cleaning removes calcium off the plates and costs almost nothing. It cannot put the coating back, because the coating is what wears out. Here is how to tell which one you are looking at before you spend anything.
Checked 63 manufacturer manuals on file Spot an error?
Read this before you open anything
Muriatic acid burns skin, eyes and lungs. Every step below assumes you have the protection on before the bottle is opened, not after.
- Add acid to water. Never add water to acid. The reverse can boil and spit acid back at you.
- Chemical splash goggles and acid-resistant gloves. Safety glasses are not splash goggles.
- Rinse the cell of chlorinated water first, and never mix acid with chlorine products. That combination releases chlorine gas.
- Power off and lock out the controller before removing the cell.
- Work outdoors or in a well ventilated area, never in a closed pump house.
- Follow your manufacturer's procedure and the product safety data sheet wherever they conflict with anything on this page.
- On exposure, flush with water for fifteen minutes and call Poison Control. In the US that is 1-800-222-1222.
Paying a pool professional to do this is a reasonable call, and a lot of people should make it. There is no prize for handling acid yourself.
First, find out whether it needs cleaning at all
This is the step almost every guide skips. Every manufacturer in our archive tells the owner not to acid wash a cell that does not need it, and two of them describe the test in the same way: put the cell in the solution and watch. Vigorous foaming means there is scale to dissolve. No foaming means there is nothing there and the acid is only costing you coating.
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Mild Acid Washing: Use only in severe cases where flushing and scraping will not remove the majority of deposits.
Hayward AquaRite, manufacturer manual
The dilution is not the same for every brand
This is the part worth being careful about. The manufacturers do not agree, and the spread is wide enough to matter: following one brand's ratio on another brand's cell can mean several times the acid its maker specifies. Find your row and use your own manufacturer's number.
Caution. No row for your brand below? Then this page does not have that manufacturer's number yet, and you should read the ratio off your own manual before you mix anything. CircuPool is in that position today. Picking the nearest row on this table is the exact mistake the paragraph above is warning you about.
| System | Dilution | In the manufacturer's words | Soak limit |
|---|---|---|---|
| Hayward AquaRite | 4 parts water to 1 part acid | In a clean plastic container, mix a 4:1 solution of water to muriatic acid (one gallon of water to one quart of muriatic acid). |
The cell should soak for a few minutes and then rinse with a high pressure garden hose. |
| Jandy TruClear | 10 parts water to 1 part acid | With protective glasses and gloves on, add one (1) part muriatic acid to ten (10) parts water in a small bucket and mix the cleaning solution together. |
Do not leave in acid for more than 30 minutes. |
| Pentair IntelliChlor | 4 parts water to 1 part acid | In a plastic bucket, create 4:1 water-to-acid solution. |
Do NOT leave acid in the SCG cell for more than 30 minutes. |
The acid on this page will never be an affiliate link. The commission would be pennies and it is the only thing here that carries a real injury risk, and selling you the hazard while telling you how to use it is not a trade worth making. Pool salt will never be one either, because the page before this one exists to stop you buying salt you do not need. The stand and the goggles below are links we earn on, and they are the two things this procedure needs that most people do not already own.
The two things this job needs that you may not have
The safety block above is specific about this: safety glasses are not splash goggles, and acid does not care about the difference.
Check current prices on chemical splash gogglesGoes to Amazon, searched for splash goggles rather than safety glasses. Paid link. I earn a commission if you buy.
A stand holds the cell upright so the plates stay covered and the acid stays in the cell rather than in a bucket you are holding.
Check current prices on cell cleaning standsGoes to Amazon, searched for cell stands. Paid link. I earn a commission if you buy.
Three signs cleaning will not save it
Scale
White and crusty, sitting on top of the plate and bridging the gap between them. This is the state an acid wash is for, and it costs almost nothing to fix.
Worn
Plates thin, patchy or bare, with the gaps between them clear. This is loss of the coating itself. No acid bath brings it back, and cleaning it is time spent on a cell that is done.
- No foaming when the cell goes into the solution. There is no scale to remove, so whatever is wrong is not scale.
- The plates look worn rather than coated. Scale is white and crusty and sits on top. A worn cell has plates that look thin, patchy or bare.
- Chlorine does not recover after cleaning, with salt confirmed by an independent test. If the reading is right and the cell is clean and there is still no chlorine twenty four hours later, the coating is gone. No acid bath brings it back, because restoring that coating is a factory stripping and recoating job.
Then what
Cleaned it, reset it, still no chlorine after 24 hours. At that point the plates are done; no acid bath brings the coating back. Find your exact replacement here.
The questions people actually ask
The questions asked at the pad, with the cell already out of the plumbing.
How often should I clean my salt cell?
Only when it needs it, and the foam test above tells you. Acid removes scale and it also removes coating, so a cell cleaned on a schedule rather than on evidence wears out sooner than one left alone.
How long do you soak a salt cell in acid?
Jandy and Pentair both state a maximum of thirty minutes in their own documents, and both warn that excessive acid washing damages the cell. Hayward's owner's manuals say a few minutes and then rinse, with no maximum stated. Use the number from your own manufacturer, which is the row in the table above.
What is the right acid to water ratio for cleaning a salt cell?
It is not the same for every brand, which is the single most dangerous assumption on this subject. Hayward and Pentair both specify four parts water to one part acid. Jandy specifies ten to one. Following the wrong manual is two and a half times the acid its maker calls for.
Can I clean a salt cell without acid?
Flushing with a hose and scraping visible deposits is what Hayward tells you to try first, and acid washing is what it reserves for severe cases where flushing and scraping do not remove the majority of deposits. Start with the gentler step for the same reason you would on anything else you cannot replace cheaply.
My cell is clean and there is still no chlorine. Now what?
If the salt tests in range and the cell has been cleaned and chlorine still has not recovered after about a day, the plates are the problem and no amount of acid brings a worn coating back. That is the point where finding the exact replacement is the honest next step.