How to Know When to Change the Filter on a Water Softener
- 1). Allow new water softeners to run for two years before testing the filter's ability. If you have moved into a home with an existing water softener, testing should be performed as soon as possible.
- 2). Take a sample of water downstream from your water softener. Use a hard water test strip according to the instructions on the packaging. If you are uncomfortable with testing your own water, contact your local water authority to send off a water sample.
- 3). Note the results of your water test which should reflect calcium carbonate levels of zero to 60 milligrams per liter (mg/L) for soft water while 61 to 120 mg/L indicate moderately hard water. Readings higher than 121 mg/L indicate hard water.
- 4). Change your filter according to the results of your water test if it is reported as hard or moderately hard following the manufacturer's directions. If your test reported soft water, then the filter doesn't need to be changed.
- 5). Repeat hard water testing annually and change out the filter when the test indicates the water coming from the softener is hard. Depending on brand and efficiency, you might expect to replace your filter annually or might be able to go for as long as 10 to 15 years without needing to change it.
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