RO Purifier Maintenance Guide: When to Change Different Filter Cartridges and Membranes?

If you are using an RO water purifier at home, you probably have water supply with high TDS levels. The RO purifier provides clean and safe drinking water by reducing the TDS levels and removing the harmful dissolved impurities. The water filter uses various stages of filtration to give you 100% pure drinking water.

Maintenance of Filters

The filters and membranes have to be maintained regularly and should be replaced as per the usage. The cost of the filter and membrane replacement is the main component of the maintenance cost as they are also the major components of the RO purification system. As the filters are an important part of a water purifier, you should be able to judge when they need be replaced to continue getting clean and safe water to drink. This is also important so that the RO water purifier serves you longer.

Factors Affecting the Replacement Schedule

The saturation of the filter and replacement depends on the following factors:

  • Impurity levels
  • TDS levels
  • Quantity of water purified

If all the three factors mentioned above are on the higher side, you need to replace the RO membrane and the filters earlier than average.

Individual Filters and Membranes

This section will outline the replacement schedule of each filter individually assuming a family size of 4-6 members:

  • Pre-Filter: This should ideally be replaced every 3-4 months.
  • Sediment Filter: Ideal replacement period is 6-12 months.

The main function of this filter is to help in removal of dirt from water. This helps in protecting the RO membrane and carbon filter from getting clogged ahead of time. Changing this filter might cost you a few hundreds, but not replacing it on time could lead to replacing the membrane, which could turn out to be very expensive.

  • Carbon Filter: This should be ideally replaced every 4-6 months.

The carbon filter is designed for removal of organic compounds, chlorine and unpleasant odor and taste that could make water non-potable. Removal of chlorine at this stage improves life of RO membrane.

  • RO Membrane: This needs to be typically replaced in 2-3 years.

Membrane is the main component of RO filter that does all the work with the help of other filters to protect it. Once the membrane has cleaned 4000 – 6000 liters of water, it should be replaced, provided the other filters have been taken care of. The life of the filter depends on the TDS content in water. TDS levels in purified water is a good indicator of the need to replace an RO membrane. Its life could be shorter if TDS levels are much higher than the capacity of the purifier.

Ideally, an RO water purifier should be used only if TDS levels in water are very high. If not so, you could be spending more on maintenance without any real advantage or benefit from so-called purified water