Considering the quality of drinking water available at most places in India, installing a water purifier at home has become a necessity.

Most of the cities, towns, and villages in India depend on groundwater to meet their requirements. Some towns do have municipalities that supply water from lakes and rivers. In any case, we should filter and purify the water before we consume it.

The groundwater in India comes with varying degrees of hardness. Therefore, you need efficient water purification techniques to eliminate the TDS from the water. Also, these filters have to contend with heavy impurities like lead, mercury, and arsenic.

There are different kinds of water purification technologies available in India. They are as follows.

  • Sediment Water purifier
  • Ultraviolet filtration
  • Ultrafiltration membranes
  • Reverse Osmosis (RO) membranes
  • Ion Exchange Mechanism

Out of the different technologies mentioned above, the RO system is the most popular one. The present-day RO water purifiers use multiple techniques to purify water. Let us understand the process of RO water purification in brief before going on to discuss ways to use your RO water purifier efficiently.

A peek into the Reverse Osmosis System

RO purification systems work on the principle of Reverse Osmosis. To understand what Reverse Osmosis is, one should have an idea about the term ‘osmosis.’ Water, or for that matter any liquid, tends to move from an area of lower concentration to a higher concentration when separated by a semipermeable membrane. It is known as ‘Osmosis.’


One of the easiest examples that come to mind is the absorption of water by the roots of the plants from the soil. The Reverse Osmosis principal works in the opposite manner.

In the RO system, water moves from a higher concentration to a lower concentration through the semipermeable membrane. As it is against the principles of nature, you need to apply external pressure to the water.


Hence, the RO water purifiers have a pump that forces water through the semipermeable membrane. This membrane has minute pores that allow molecules having a molecular weight below 20 to pass through thereby trapping the heavier molecules.

Most of the salts and the contaminants have a molecular weight of more than 20. Hence, you get pure water (Molecular weight of water = 18) on the other side of the membrane.

Need to maintain the RO water purifier properly

The water from the source contains various impurities like TDS, heavy metal impurities, and other contaminants. The TDS comprises of minerals like Calcium, Magnesium, and so on. It also includes nitrates, chlorides, carbonates, and sulphates, and so on.

The heavy metals comprise harmful substances like arsenic, lead, and mercury. The RO membrane traps these impurities and allows pure water to pass through. Therefore, these salts and metals tend to accumulate on the filter surface.

Yes, the RO water purification has a ‘Reject Water’ system in place that discards the part of water containing these impurities. However, over a period, these contaminants can clog the RO membranes thereby reducing its efficiency. Therefore, it becomes necessary to maintain the RO water purifiers.

Different Parts of the RO water purifier

Any RO water purifier of good quality uses a 6-stage or 7-stage water purification process. Let us understand these stages as it can help us in maintaining the water purifying system.

Sediment FilterPre-Activated Carbon FiltersRO Membrane

This filter is a regular candle filter usually fitted outside the appliance to take care of the visible and heavy impurities. This filter traps the mud particles and other visible contaminants and prevents them from gaining entry into the RO water purifying system.

The source water can have an unpleasant smell because of the various contaminants. This water passes through the Pre-Activated Carbon filter before entering the RO membrane.

The RO membrane is the heart of the machine where the main action takes place. It consists of a semipermeable membrane that traps the heavy impurities and TDS while allowing pure water to flow out from the other side.

Ultrafiltration membrane (UF)

The UF membrane traps any residual impurity that manages to sneak through the RO membrane. This membrane has minute pores that allow only pure water to pass through.

Ultraviolet Lamp

The RO purified water passes through the UV chamber where the UV radiation kills the bacteria and the viruses thereby ensuring you have healthy water to drink.

Post-Activated Carbon filters

These filters have the responsibility of eliminating the bad odour from the purified RO water.

When you maintain your water purification system, you have to ensure the maintenance of all these different types of filters. All these process work in cohesion. Let us now see how to maintain your RO water purifier. Many aspects go into the maintenance of your RO water purifier.

Test the Water Quality

It is vital to test the quality of water in your area before you purchase your water purifier. For example, if the level of TDS in your water source is less than 500 ppm, there is no need for you to purchase an RO water purifier. You can use a UV water purifier/UF water purifier. They are equally effective, especially when you do not have water with high levels of TDS.

The positioning of the water purifier is crucial

A lot depends on where you place the water purifier. In India, the wall-mounted water purifier is more common as compared to the Under the Counter water purifier. The common kitchen has enough space for a wall-mounted water purifier whereas the ‘Under the Counter’ water purifiers are ideal for the modern modular kitchens.

The temperature of the place where you place the water purifier is also critical. If the area is a moisture-laden one, there are chances that the water can freeze during the winter months.

Maintaining the water pressure

Reverse Osmosis technology requires the presence of a semipermeable membrane. The RO membrane is the most expensive part of the water purifier. You need to apply pressure for the water to pass through the membrane.

Ensure that you use the right amount of pressure as excessive pressure can damage the membrane. Therefore, it is critical to verify the inlet water pressure before you install the RO water purifier.

Change the filters on time

A properly maintained RO water purifier can last for a minimum of 10 to 15 years. You should pay proper attention to the individual filters to ensure that they last longer. We have already seen that the RO water purifier comes with 6-stage or 7-stage water purification.

Pay careful attention to the owner’s manual and note down which filter is due for replacement, and at what time.

Sediment Filters

These filters have a vital role to play. They trap the heavy and visible impurities and prevent them from entering the RO water purifier. Therefore, they protect the expensive RO membrane. In the process, these filters accumulate a lot of dirt and silt. Hence, you should replace these filters every 12 months.

Carbon filters

The pre-activated and the post-activated carbon filters help in removing the putrid odour. These filters also serve to remove the chlorine and other contaminants that can affect the taste of water. They also need replacement every 12 months.

Reverse Osmosis Membrane

The semipermeable RO membrane is the most crucial part of your RO water purifier. They perform the most challenging task of eliminating TDS, heavy metal impurities, and even bacteria and viruses from the water.

If you change the sediment and carbon filters every 12 months, the RO membranes can efficiently work for 2 to 3 years. Therefore, you should replace the RO membrane once every 2 to 3 years depending on the load it carries. Remember that these membranes are the most expensive parts of the appliance as well.

Ultra-filtration membrane

This membrane works as a polishing filter as it removes the residual impurities if any. These filters placed after the RO membrane, have the responsibility of providing pure and tasty water. You should replace them along with your RO membranes every 2 or 3 years.

Ultraviolet Lamp

This chamber is responsible for eliminating the bacteria and viruses. Replace the lamp whenever it stops functioning. In the ordinary course, you would not find the need to replace them frequently.

Clean your water purifiers regularly

One way of enhancing the life of your RO water purifier is to keep it clean. Engage the services of professionals to clean and sanitize the water purifier regularly. It will prevent the spread of infections. You can also do this process at home on your own. We shall go through the simple process in detail.

1. Switch off your RO water purifier and unplug the wires as a safety measure.

2. Shut off the main valve entirely as it can result in unnecessary spillage of water.

3. It is better to empty the storage tank by draining all the water out of the water purifier.

4. Remove the sediment as well as the carbon filters from their locations

5. Remove the RO membrane from the housing.

6. Keeping the filters out of their housings, screw the housings back into their respective locations.

7. Pour one cup of (H2O2) Hydrogen Peroxide into the first stage housing.

8. Reattach all the connections and turn the main valve on again.

9. Allow the system to run in the absence of the filters and ensure that the storage tank becomes full.

10. Let the system run through a minimum of two cycles.

11. Shut the main valve again and install the filters (Replace them if necessary with new ones).

12. Allow the tank to fill up once. Drain the tank and let the tank fill up again.

Your RO water purifier is now ready for use again. Repeat this process every year when you change the filters. Use original filters alone. You will find a lot of spurious filter membranes available in the market. They are inexpensive but can cause significant harm to the machine. It affects the quality of the water output.

These handy tips can help you maintain the RO water purifier for many years. These appliances do a commendable job of maintaining the health of your family by ensuring supply of pure water. It is our responsibility to preserve these appliances in perfect working condition.