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Laswim EC Series Salt Chlorinator Showing E4: What Should You Do?

Last updated: 3 Oct 2026
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Salt Chlorinator Error Codes | Laswim EC Series

Laswim EC Series Salt Chlorinator Showing E4: What Should You Do?

The E4 code indicates salt concentration is too high. Before draining any water, test the actual salt level to confirm, then adjust as needed.

E4
Meaning per the manual

Salt Concentration Too High

E4 is a warning code, not a salt reading. Use a separate test device to find the actual salt level.

Normal salt level per the manual
3,500 ppm
Laswim EC Series

3 Steps to Lower Salt Correctly

1
Test the actual salt level in the pool
Use a salt meter or a dedicated salt test kit to confirm the salt really is high. Dont decide to change water based on the display code alone.
2
If salt really is high, dilute with fresh water
Drain part of the pool water and refill with fresh water. Calculate the amount to replace from the measured salt level and pool volume, or ask your pool caretaker to assess it.
Drain some water Refill with fresh water Circulate to mix Retest
3
Circulate thoroughly, then retest
Test the salt level again. Once it is back to normal, the manual says the E4 code should clear and the unit should resume operation.

How to Estimate How Much Water to Replace

When refilling with fresh water that contains almost no salt, the calculation is:

Water to replace (m³) = Pool volume (m³) × (measured ppm 3,500) ÷ measured ppm
Worked example

A 50 m³ pool measures 4,500 ppm and needs to come down to 3,500 ppm

50 × (4,500 3,500) ÷ 4,500 11 m³

Approximate Water Replacement Table

Target 3,500 ppm, calculated with the formula above (unit: m³)

Measured salt level
20 m³ pool
50 m³ pool
100 m³ pool
4,000 ppm
2.5
6.3
12.5
4,500 ppm
4.4
11.1
22.2
5,000 ppm
6.0
15.0
30.0

Figures are theoretical estimates assuming the refill water contains almost no salt. Replace water in portions and retest after it has mixed.

How Is E4 Different From E5?

Both codes relate to salt level, but are fixed in opposite directions.

E4 This article
Salt too high
Confirm by testing, then dilute with fresh water
E5
Salt too low
Confirm by testing, then add only the salt needed
Salt Is Normal but E4 Still Shows

Have a technician check the unit before draining any more water, to find the real cause.

E4 is a warning code, not a salt reading. Use a separate test device to find the actual salt level.

Switch off and disconnect power before maintenance. Internal inspection should be done by a qualified technician.

Frequently Asked Questions

What does the E4 code mean on a Laswim salt chlorinator?

E4 means salt concentration is too high. Test the actual salt level to confirm before draining water.

Do I need to change the water right away?

Not yet. Test the actual salt level with a meter or test kit first. Dont decide to change water based on the display code alone.

If salt is really high, how do I lower it?

Drain part of the pool water and refill with fresh water, calculating the amount from the measured salt level and pool volume. Then circulate thoroughly and retest.

What salt level should a Laswim EC Series run at?

The Laswim EC Series manual specifies a normal salt level of 3,500 ppm.

Salt is normal but E4 still shows. What should I do?

Dont drain more water. Have a technician check the unit to find the real cause.

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Laswim EC Series Salt Chlorinators

Looking for a Laswim EC Series salt chlorinator, or want to compare models for your pool? See the full product details on our EC Series salt chlorinator page.

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Ask our team on LINE before you decide

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