Understanding salt chlorinator faults
Separate displayed warnings, low chlorine production and water-balance problems before replacing a cell or controller.
Use this guide to
Record useful evidence, complete safe checks and recognise when the pool or equipment should remain out of use.
Important limit
A symptom helps narrow the fault. It does not prove which part has failed, whether the water is safe, or whether underground pipework is sound.
Safety first
Switch equipment off if a cell housing leaks, wiring is damaged, the controller smells burnt or protection trips. Do not open the controller, bridge a flow switch or mix acid and chlorine products. Clean a cell only by the manufacturer method.
Start with context
Observe before changing settings
A low-salt warning, no-flow message or low chlorine reading does not automatically prove a failed cell. Water temperature, flow, salt concentration, scale, run time, output setting, cell age, wiring and controller condition all affect operation.
Safe first checks
Observation is not confirmation
What the signs actually mean
A symptom is just a clue. We still need to test the system properly before we rip anything out or start pouring chemicals in.
| What you observe | What may cause it | What confirms the next step |
|---|---|---|
| Low-salt warning | Low salt, cold water, scaled or aged cell, calibration difference, poor connection or controller fault. | Compare an independent salinity test with the model range, inspect the cell and measure electrical output. Do not add salt from the display alone. |
| No-flow warning | Pump off, air in cell, dirty filter, closed valve, low speed, flow-switch fault or incorrect cell orientation. | Verify hydraulic flow and air removal first, then test the switch and controller input. |
| Cell operates but chlorine stays low | Insufficient run time or output, high demand, algae, poor stabiliser control, scaled cell, ageing cell or circulation gaps. | Test full water chemistry, calculate production against operating hours and inspect the pool and cell before condemning equipment. |
| Controller is blank or trips | Supply fault, protection device, internal power section, moisture, cable or connected-cell fault. | Leave isolated and arrange electrical and controller testing. Do not open the enclosure. |
Practical sequence
Complete only the checks that are safe
Capture
Record the complete display before resetting anything. Intermittent codes are useful diagnostic evidence.
Verify water
Obtain independent chlorine, pH and salt results. A displayed value is not a full water test.
Inspect flow
Check for a full cell housing, clean accessible baskets and normal return flow.
Test system
Assess chemistry, cell condition, output and controller together before selecting a replacement.
Stop and arrange help
Do not keep operating or dosing through these conditions.
What remote review can do
Interpret the manual meaning of a photographed code for an identified model.
Compare visible flow, output setting and independent test results.
Identify whether more water and equipment data are required before a service visit.
What cannot be confirmed remotely
Measure cell current, controller voltage, coating condition or flow-switch operation.
Confirm cell life from age or appearance alone.
Prescribe salt addition safely without a reliable independent test and pool volume.
Prepare useful evidence
Clear records reduce guesswork. They do not replace on-site testing where pressure, flow, electrical condition or water integrity must be measured.
Related help
Continue with the right service or tool
Real questions
Frequently asked questions
Where an answer depends on a measurement or site condition, the limit is stated.
Does a low-salt light mean I should add salt?+
Not by itself. Cold water, scale, cell wear, calibration and electrical conditions can affect the warning. Confirm salinity independently before adding salt because excess salt may require water replacement.
Can I scrape scale off the cell plates?+
No. Scraping can damage the electrode coating. Follow the manufacturer cleaning method and dilution exactly, and avoid unnecessary acid exposure because it can shorten cell life.
Why is the chlorinator working but the pool is green?+
Displayed operation does not prove adequate chlorine residual throughout the pool. Output, run time, circulation, stabiliser, pH, algae load and cell production must be checked together.
Should the cell bubble?+
Some visible gas formation can occur during chlorine generation, but appearance varies by cell and flow. Bubbles do not prove correct chlorine output or exclude a fault.
Need measured confirmation?
Send the observations before the visit
Include the address, equipment labels, wide photos, close photos, readings and what changed before the problem started. Palatial Pools will confirm what can be checked remotely and what needs an on-site test.