Chlorinator Off No Cell Power

Two different faults hide behind this one search phrase, and they do not share a fix. Either the control box itself is dead, blank display, no Power LED, nothing at all, or the box is powered and showing you something while the cell makes no chlorine. The first is a supply problem at the panel and gets settled with a voltmeter. The second is almost always flow, water temperature, a cord, or a worn out cell, and a voltmeter tells you nothing about any of those. Work out which half you are in before you spend a dollar.

Decide which half you are in

Stand at the panel and look at the face of the unit once, carefully. Blank display and no light lit anywhere means you are in the dead controller case. A lit display, any LED on or blinking, a salinity number showing even a clearly wrong one, means you are in the powered but not generating case. A unit that lights up on its own and then drops out when the pump starts is still the second case.

The two paths do not overlap. Nothing on the flow and temperature checklist will revive a blank panel, and no amount of voltage testing at the input terminals will make a lit panel start producing chlorine.

The dead controller: input voltage first, fuse second

For a panel with no Power LED, the clearest published sequence we have is from Leslie’s troubleshooting guide for the AquaRite: “If the Power LED does not illuminate, make sure the voltage is correct. The screw terminals at the control require either 120VAC or 240VAC input power. Verify the voltage with a voltmeter. If there is input power, but the Power LED still isn’t lighting up, it may have blown a fuse.”

Read the order in that. Supply first. Fuse second. Plenty of people do it backwards, buy a fuse, fit it, and then discover the breaker had tripped or the time clock feeding the unit had simply rolled over to off.

Here is the boundary, and we will say it once. Confirming supply voltage at those terminals means opening a live panel and putting probes on energized screws. That is electrical work. If you are not comfortable with a voltmeter on live terminals, stop and call a licensed electrician. Nothing else on this page asks you to open the box.

There are two things you can check with the power off and no meter at all: the breaker feeding the equipment pad, and whether the chlorinator is wired downstream of a timer or relay that is currently off. A unit fed through the pump timer has no power whenever the timer says so. That is not a fault.

The powered panel that will not generate: an order you can follow

1. Mode and temperature. Output set to 0%, or a service or off position, is the unit doing what it was told. Then look at the water temperature, because cold is the most common reason a healthy system produces nothing in spring and fall. Hayward’s AquaRite manual states it plainly: “The Aqua Rite automatically stops generating when the pool water temperatures drops below 50ºF.” In practice the floor is higher. In The Swim writes that most salt cells will not work well in water below 60 degrees, which is the more useful number to plan around and the reason we keep a separate page on what temperature a salt cell stops working.

2. Flow. No cell is allowed to run without proof of water moving past it. The AquaRite manual asks for at least a 12 inch straight pipe run upstream of the flow switch with the arrow pointing with the flow, and it distinguishes a steady no flow LED from a flashing one, where flashing is just the 15 to 60 second startup delay. A switch mounted too close to an elbow, or installed backwards, can fail to satisfy while the pump runs perfectly. If the panel is complaining about flow, start at our page on the flow switch for a salt cell rather than at the cell.

3. The cell cord. Unplug it at the panel, look at the pins, seat it firmly. We are flagging this as a common sense check, not a sourced one: none of our approved sources covers cell cords or connector faults, so we are not going to pretend there is a published procedure for it.

4. The cell itself. Scale on the plates and plate wear both cut output. If everything above is clean and the unit still will not make chlorine, that is the point to work through why a salt cell is not producing chlorine and to test the salt cell as its own component instead of guessing from the display.

The panel is inferring salinity, not measuring it

This is the part that sends people to the store for the wrong thing. There is no salt sensor in a salt system. Orenda explains that the cell reads conductivity and back calculates a salinity number, temperature compensated, so cold water conducts less and the panel reads low while not one grain of salt has left the pool. Scale and plate age do the same thing from a different direction, which is why a LOW SALT warning is frequently not low salt at all.

The practical consequence: the number on a struggling panel is describing the cell’s condition as much as the water’s. Confirm salinity with an independent test before you buy anything, and if the water genuinely is low, size the addition with our pool salt calculator rather than by adding a bag and hoping.

What each failure path costs

A reader at a dead panel is really asking which part to buy. River Pools publishes both sides of that fork, and the numbers are close enough together to change the decision.

Those figures come from River Pools on how long salt chlorine generators last, which also makes the point that matters most here: a complete new generator costs only a couple hundred dollars more than a cell alone. If your cell is at the end of a 3 to 7 year run and the board is the same age, buying the cell by itself is buying half a system. Our pages on what a salt cell costs and on salt cell replacement go through that math in more detail.

One caution before you order anything. In The Swim’s rule is to replace the cell when output stays down with a clean cell and sensor, correct balance, correct salt and warm enough water. Every one of those conditions has to be true first, or you are replacing a part that was never the problem. And if you plan to clean the cell first, go easy on the acid, because acid that is too concentrated erodes the coating off the titanium grids. Our guide to cleaning a salt cell covers the mix.

What we cannot tell you from these sources

The troubleshooting guide quoted above covers a dead Power LED, a flashing Generating light, HOT and COLD displays, No Flow alerts, Check Salt, High Salt and Inspect Cell. It says nothing about transformers, nothing about cell cords, and nothing about what a “no cell power” message means on any particular unit, so we are not going to attribute those to it. Panel wording varies by manufacturer and by model year. Your own manual is the authority for what your screen is actually telling you, and the rest of the salt cell hub is built to sit alongside it, not to replace it.

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