How to Clean Salt Cell?

Shut the pump off, pull the cell, and look at the plates before you mix anything. If the deposits are light, Hayward’s manual says to flush them off with a high pressure garden hose and stop there. Only if scale remains do you go to acid: 4 parts water to 1 part muriatic acid, soaked “for a few minutes,” then rinsed. Always add acid to water, never the other way around, and never touch the plates with anything metal.

That is the whole job. The rest of this page is the parts people get wrong, starting with the biggest one: cleaning a cell that did not need it.

One note on names. Chlorine generator, salt chlorine generator, salt chlorinator and salt cell all describe the same hardware, and cleaning a chlorine generator means cleaning the cell inside it. The control box on the wall never needs cleaning, only the plates in the pipe. If you have not had the cell out before, our page on how to install a salt cell shows how the unions come apart.

When to clean, and when to leave it alone

Hayward asks you to inspect the cell every 3 months, or whenever you clean the filter. Inspect is the operative word. An inspection that ends with you putting the cell straight back in is a successful inspection.

Clean when you can see white or grey crust bridging the plates, or when the panel reports low salt and a real water test says your salt is fine. Do not clean because it has been three months, or at closing to be safe, or because chlorine is low before you have ruled out cyanuric acid, which is the more common answer: cyanuric acid for pool.

Be strict about this, because an acid soak is not free. Acid dissolves calcium scale, and it does not perfectly distinguish the scale from the coating underneath. That coating is the working surface, and it is what you eventually pay $700 to $1,100 to replace, per River Pools. Hayward telling you to hose first and then soak for a few minutes rather than an hour says how gentle this is meant to be. Acid soaking four times a season shortens the cell’s life to solve a problem you mostly did not have.

Most cells are self-cleaning, reversing polarity on a schedule so deposits shed off the plate that grew them. Your job is to catch what that loses ground on, which in hard water at high pH is a lot more than at pH 7.4.

What you need

• A garden hose with a decent nozzle
• Muriatic acid, the same stuff you use to lower pH
• A clean plastic bucket, or the cleaning cap that came with the cell
• Water, measured, because the ratio matters
• Eye protection and gloves, and outdoor air

Nothing on that list is a wire brush, a screwdriver or a putty knife. Hayward is explicit: never use metal tools, because they scratch the coating. A scratch is permanent, and it is a spot that will never make chlorine again.

The procedure

1. Kill the power at the breaker, not just the panel. Shut the pump down and close the valves either side of the cell if you have them.

2. Unscrew the unions and pull the cell out. Note which end pointed toward the pump. Some cells care about orientation when they go back.

3. Rinse it hard with the hose, through both ends. This is the whole treatment for light deposits. Point the nozzle straight down the plate channels rather than across them. A surprising amount comes out this way: hair, leaf fragments, and calcium flakes the polarity reversal already loosened.

4. Look at the plates in daylight. Dark grey and smooth means you are done. Reinstall. White crust still bridging the plates means continue.

5. Mix 4 parts water to 1 part muriatic acid. In a bucket, or in the cell itself with a cleaning cap on the bottom end. Water in first, then pour the acid in slowly. Hayward puts this in capital letters and so will we: “ALWAYS ADD ACID TO WATER - NEVER ADD WATER TO ACID.” Water into acid can flash and spit concentrated acid back at your face.

6. Cover the plates and watch it. You will get vigorous fizzing as the acid hits carbonate scale. That fizzing is the reaction working. Hayward’s soak time is a few minutes.

7. Stop when the fizzing stops. There is no more scale to dissolve, and everything after that is contact time with the coating for no benefit. If heavy scale remains, dump the solution, rinse, and do a second short soak with fresh mix rather than leaving the cell in an exhausted one for an hour.

8. Rinse thoroughly with the hose, into the yard or a drain, not into the pool.

9. Reinstall, hand tighten the unions, open the valves, and start the pump before powering the cell. Look for leaks, then check the salinity reading once the water has turned over.

What clean plates look like

Dark grey to near black, uniform, smooth, with clear open channels between them. That dark surface is the coating. It is supposed to look like that.

What you do not want is bare, bright metal. That is titanium showing through where the coating has gone, and no amount of cleaning brings it back. Plates that are patchy, silvery in stripes, or visibly thinned say the cell is near the end of its life rather than dirty, which is the subject of how long does a salt cell last.

Check for damage while it is out: cracked housing, a bent plate, corroded terminals in the connector. Any of those move you to salt cell replacement.

Can you use vinegar to clean a salt cell?

Honest answer: it does something, and it is probably not worth it.

Household vinegar is about 5% acetic acid. Muriatic acid at 4:1 is far stronger and far faster. Vinegar will slowly lift a light film given hours of soaking. It will not clear hardened calcium bridges in a few minutes, and Hayward’s manual does not name it, so if a warranty claim is in play the manual specifies muriatic acid at 4:1.

There is also a logic problem. Deposits light enough for vinegar are light enough for the hose, and the hose is step three anyway. Deposits heavy enough to need help are heavier than vinegar handles. What you get is a very long soak, and soak time is the thing you were trying to minimize.

Vinegar earns its place if you are nervous about handling muriatic acid or have nowhere safe to work with it. Slower, safer and weaker beats not cleaning at all. Just know you are making that trade rather than getting the same result for less risk. Commercial cell cleaners are mostly dilute acid, sold at a premium over a jug of muriatic acid, and what you are buying is the pre-mixing.

If the plates are clean and the panel still complains

Clean plates plus a persistent low salt warning means the problem was never scale, and adding salt at this point is how people end up at 5,000 ppm.

Check in this order. Water temperature, because Hayward states its unit “automatically stops generating when the pool water temperatures drops below 50ºF” while Orenda puts most cells alarming or shutting off between 55 and 59°F. Then flow, because a dirty filter or a closing valve starves the cell. Then the cell type set in the menu, which rescales the whole salinity reading if it is wrong. Then a real salt test, since the panel infers salinity from cell conductivity rather than measuring it, and Orenda recommends verifying with a separate salinity meter.

Only then reach for a bag. Owners on Inyo’s thread about reducing salt show what skipping the sequence costs: “I added to much salt to my 15000 gallon pool because I did not realize my T-cell was going bad.” If the test really does show you low, size the dose with the pool salt calculator rather than by the bag.

Why the panel can be confidently wrong is on salt cell for pool, and getting the inspection into a routine you follow is on salt water pool maintenance.

Where to go next