Does Reverse Osmosis System Require Maintenance?

A reverse osmosis system uses filters and an RO membrane to purify water. It reduces sediments, heavy metals, chemicals, bacteria, and other contaminants from your drinking water.

You need to maintain the system regularly if you want it to last longer. Regular maintenance helps keep it performing to the fullest capacity.

You should replace the filters once or twice a year depending on the quality of the feed water, replace the RO membrane every 2 to 3 years and check the pressure of the storage tank yearly.

In this post, we discuss the RO system maintenance routine to help you keep your system in good shape.

Reverse Osmosis System Maintenance

Filter Changes

One of the most important ways of maintaining a reverse osmosis system is regular filter changes.

The number of times to change the pre and post-filters depends on the condition of your feed water and the rate of your water consumption.

High levels of sediment or water hardness can lower the condition of the pre-filters significantly. Additionally, the more you use the water for cooking and drinking, the faster the filters will wear out.

So, how often should you replace the filters?

Does Reverse Osmosis System Require Maintenance

1. Pre-Filters

Pre-filters separate dust, sand, silt, and other residual particles in the water. The pre-filter stage is highly important as it helps protect the RO membrane from damage (The particles can clog the membrane) by these particles.

A carbon filter is also used in this stage to remove chlorine from your water. Chlorine affects the performance of the RO membrane as well.

Thin-film composite membranes are susceptible to free chlorine. Therefore, ensure that you replace the pre-filters every 6 to 12 months.

It is essential that you purchase the right filters for your system since cheap filters tend to wear out faster. Always double-check when getting replacements to ensure they are up to standards.

Failure to replace the pre-filters in time can lead to:

  • Decrease the overall purity of your water.
  • A drop in the output water volume.
  • Accumulation and growth of waterborne pathogens like mold and bacteria in the system.
  • High wastewater production leads to high water bills.

2. Post Filters

Most RO systems have 1 or 2 post-filters. The 1st post filter is usually a carbon filter that further eliminates any smell or tastes that might be lingering in your water.

Higher-end models feature an alkalizing or remineralizing stage, which restores beneficial minerals into the water. Such systems make the best options for persons who can’t stand mineral-free water.

Carbon post-filters require replacement every 12 months. Some can even last for up to 2 years.

Remineralizing filters should be replaced every 6 to 12 months, depending on how often you use the system.

Failure to replace the post-filters can lead to:

  • Decrease in the overall output.
  • Smelly and foul-tasting water.
  • More wastewater
  • Growth of bacteria and other harmful microorganisms.

How to Replace Filters

The process of replacing pre and post-filters is relatively easy. In fact, it will most likely take you less than 10 minutes to get everything done.

To carry out the task even faster, check the product manual. You’ll most likely come across step-by-step instructions on how to filter and membrane replacements.

Here is a basic idea of how the process should be (it could be different in different models):

  1. Turn off the water supply.
  2. Depressurize the RO system.
  3. Remove the filters from their housings.
  4. Insert new elements and screw on the housings back.
  5. Turn on the water supply.
  6. Open the faucet and leave the system to flush for a few minutes.
  7. Check for leaks.
  8. Close the faucet and refill the tank.

Reverse Osmosis Membrane Maintenance

The reverse osmosis membrane, the central part of the RO system, also requires maintenance to work efficiently. It separates solutes from solvents allowing only pure water to pass through.

It’s only when the membrane is clean that you’ll get clean, purified, and fresh water.

You can clean the RO membrane every 3 to 4 months. Cleaning it properly makes it last longer. However, you must replace it every 2 to 3 years.

The fastest way to determine whether your system’s membrane requires changing is using a TDS meter. If the TDS of the output water drops below 80%, it’s time to replace the membrane.

To find out how to replace your unit’s membrane, consult the manual.

Cleaning and Sanitizing the RO System

Cleaning and sanitizing your reverse osmosis system is not necessary in all cases. However, to be safe, clean the unit at least once a year or when replacing the filters.

The process is neither too complicated nor time-consuming.

To clean the system, follow the product’s manual or the instructions we’ve outlined below.

  1. Turn off the water supply.
  2. Depressurize the system – open the nozzle and let the water flow out.
  3. Remove the filters and clean the housings with warm soapy water. Rinse with clean water until all the soap is gone.
  4. To sanitize it further, you can add some bleach into the housing.
  5. Close the system with the filters out. Next, turn on the water supply.
  6. Open the faucet and allow water to start flowing out. After a few seconds, close it and check for leaks.
  7. Fill the storage tank and let the sanitizer sit in for 1 to 2 hours.
  8. Open the faucet and flush all the water out.
  9. Repeat the refilling and flushing out of the water several times until you get all the bleach out.
  10. Repeat the 1st and 2nd steps and reinstall the filters into the housing.
  11. Turn the water on and check for leaks.

Checking the System’s Storage Tank Pressure

Enough storage tank pressure is important for an RO system. It enables it to function as intended.

That’s why you need to check the pressure of your unit’s storage tank once every year. A low-pressure gauge should help you carry out the task.

Always the pressure on your tank when it is empty. It should have a reading of 6 to 8 psi. If under pressurized, use a bicycle pump to fix it.

Reverse Osmosis Service

Although most individuals choose to maintain their RO systems, hiring a local specialist to do the job is an option.

There are so many service providers out there from different companies that do the work for you. Just reach out to a few and compare the prices.

Frequently Asked Questions

Q1. How Much Does RO Maintenance Cost?

A reverse osmosis system maintenance cost range from $50 to $200 per year. The expenses can be higher if the unit comes with more filter stages.
Also, replacing filters with a modular design is a little pricey because you have to dispose of the entire housing.

Q2. How Often Should You Flush Your RO System?

You should flush your reverse osmosis system every 2 weeks. This will help maintain the quality of your drinking water.

Q3. Do you need to add anything to reverse osmosis water?

Not necessarily. Reverse osmosis is clean, pure, and healthy for drinking, especially for persons who like mineral-free water.
However, if you can’t stand the bland taste of the water, you can remineralize it so you can enjoy the taste and get the essential minerals that your body requires.
To remineralize the water, add a mineral-rich salt like Himalayan pink salt, a few drops of minerals, or use an alkaline pitcher.

Q4. How long does a reverse osmosis tank last?

A reverse osmosis tank can last up to 10 years. In fact, most are usually warrantied for up to 5 years. After that, you just need to sanitize it once per year to remove any build-up that could have accumulated in the interior.


Reverse osmosis systems require maintenance to function effectively and last longer. Try to replace the filters every 6 to 12 months and the reverse osmosis membrane every 24 to 36 months.

It is also important to sanitize the system’s water tank annually. If possible, cleanse and reassemble the plumbing every 2 years and regularly check the tank’s pressure.

Failure to maintain the system affects the performance and quality of your output water. But with proper maintenance, the system will last for more than 10 years.

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