Importance of Sanitizing Reverse Osmosis Systems

At first thought, it might not make sense to have to clean your water purifier, as the system’s goal is to purify water. One would think that there would be no need to clean a purified water tank or any of the associated housing. However, that is unfortunately not the case. It’s easy to overlook the importance of sanitizing reverse osmosis systems. In other cases, there may be extenuating reasons for you to clean the system. For example, you might suspect that your water has exceptionally high mineral contents if you have forgotten to change filters. Similarly, you might have left standing water in the tank for extended periods of time. Bear in mind that this list is not exhaustive and that there may be many reasons for you to clean and refilter your reverse osmosis water filter.

 Tips Before You Start:


  1. If you are planning on sanitizing your system concurrent to when new filters will be installed, ensure that you keep them out of the way until it’s time to actually use them.
  2. Ensure that the area you are working in is free of any excess dirt or dust.
  3. Wash hands with soap and water.


Sanitization Steps:


  1. Turn off the cold water supply line to the residential reverse osmosis system.
  2. If your system is connected to your refrigerator, turn off that line as well.
  3. Open the RO water system faucet and allow all water from the system and storage tank to be drained.
  4. Once the system is empty, be sure to place the RO faucet back in its off position.
  5. Unscrew the housing from the pre-filter area. This is usually the filter in the closest proximity to the feedwater line. Remove the pre-filter. After the sanitization process, you will replace this pre-filter with a new one.
  6. Remove all remaining filters and the reverse osmosis membrane. If you happen to have an inline post filter installed, leave the old filter in place. 
  7. Reconnect all empty housings to the sanitation system except for the pre-filter housing. At this point, there should be no filters in any housing.
  8. Pour the packet of your choice of Sanitizer solution directly into the pre-filter housing. Or, add two or three tablespoons of bleach to the pre-filter housing (5.5% unscented bleach).
  9. Reconnect the pre-filter housing back onto the system with the sanitizer solution still inside.
  10. Turn on the cold water supply line for the system to fill with the sanitizing solution.
  11. Check for any leaks.
  12. Allow the system to fill with water. The time it takes the tank to fill will vary on water pressure. In most cases, the system should be full within 5-10 minutes. Remember that there should still be no filters in the system at this point.
  13. Turn on the RO faucet until water begins to flow. Then, turn off the faucet.
  14. If using a sanitizer solution, let the system set for at least 60 seconds. If using bleach, let the system set for at least 30 minutes.
  15. After it has set for an adequate time, flush the system by turning on the RO faucet and letting water run throughout the system until the odor of bleach is gone.
  16. Turn off the cold water supply line. Then turn on the RO faucet. Drain the system completely. Repeat this step twice to three times, as necessary.
  17. After draining the system completely the last time, replace or reinstall all filters and membrane.
  18. Turn on the cold water supply line and check for leaks.
  19. Allow the system several hours for the RO membrane purified water to refill the storage tank.


Below are some other things to keep in mind:

Strange Sounds


Strange sounds are often reported during the purging process. These may come in the form of smacking, sloshing, or sucking sounds. Be aware that this a completely typical symptom of purging. This sound is simply the negative water pressure exiting the system and making sucking noises through the filters and membrane. As soon as water enters the system and fills up, the noise should stop as a result of the balance of pressure. If the noises do not stop after this, consider calling a professional.

Weaker Pressure


Keep in mind that comparing the water pressure between the water supply source pipe and the reverse osmosis faucet is futile. Because of how the reverse osmosis system works, there will always be lessened water pressure and flow than the source water system or a regular unfiltered faucet.

Fridge And Icemaker Connections


You must make sure that the connections for the Reverse osmosis filter are disconnected from the fridge or icemaker. Not doing so may lead you to have contaminated ice as the system is purged. For that reason, double-check that all the connections are cut and only connected after the system has been fully purged and set.

Set Period


Many do not understand what the set period is for. This period is to allow the full fluids caught in the filters to run out of the system. For some mixtures, this time may be decreased due to the finer particulate and consistency of the mix. With bleach, it will take more time, as this is most often a much thicker liquid.

Bleach And Cleaner Amounts Are Specific!


Remember that when filling your system with whatever cleaning solution, those amounts are specific. You will not be getting the system cleaner by using more of this solution. Instead, you are increasing the chances it will stay in the system after purging. As such, always refer to the amounts listed either on the bleach bottle or container your cleaning solution came in.

Cleaning your reverse osmosis is an extremely involved, complex, and important task. However, if you follow the instructions above carefully, you will easily replace the filter on your own. We hope this article has helped address the importance of sanitizing reverse osmosis systems and has provided you with adequate instruction. Contact Premier H2O for more information on reverse osmosis systems.

Importance of Sanitizing Reverse Osmosis Systems