Commonly Asked Questions or FAQs Regarding Reverse Osmosis Systems



We’ve been discussing all things relating to RO in recent blog posts, but thought we would tackle a few more inquiries that have yet to be addressed. The following are commonly asked questions regarding Reverse Osmosis (RO) Drinking Water Systems: Where is an RO unit stored? Can RO hook up to a fridge or ice machine? Is RO noisy?

1. Where is an RO system stored and how does RO treat my water?

A reverse osmosis system is generally installed and stored under the kitchen sink. Under-counter reverse osmosis systems have a holding tank and several filter phases.  Here’s a basic description of what happens during the different “phases” of an RO system:

The first phase (pre-filtration) is designed to protect the membrane by reducing fine suspended materials that can clog it.  

The second phase usually entails filtration to remove chlorine that can damage thin film-material membranes.

The third phase is a semi-permeable membrane to remove a wide variety of both aesthetic and health related contaminants.

Next is a pressurized storage tank to hold the treated water. And finally, there is a carbon post-filtration phase to remove any remaining aesthetic taste or odor.

Free Water Test2. Can an RO system hook up to my fridge and/or ice machine?

If you’re wondering if an RO system can hook up to a fridge or ice maker…yes! An under-counter reverse osmosis system is plumbed to the incoming cold water line, drain, and an independent faucet. A water treatment specialist can also plumb the RO unit to your fridge and/or ice machine.

Your water treatment specialist will most likely run a ¼-inch tube from the under-sink RO unit to your fridge. But pressure is a consideration with some refrigerators, so be sure to consult with your authorized dealer or your owner’s manual because the pressure from the RO unit is about two-thirds of the incoming line pressure.

3. How large is an RO tank and how much water does it produce each day?


The typical under-counter reverse osmosis tank is 12″ diameter x 15″ tall. The RO system will operate under water pressure ranging from 40 and 100 psig and generate 10–75 gallons (45-340 Liters) per day. 

4. Is a Reverse Osmosis System Noisy?

A reverse osmosis system is very quiet though you may hear a “gurgling” sound as the “concentre” or waste water flows from the membrane to the drain. RO systems are designed so that “crossflow” water flushes the concentrated contaminates away from the system. This flushing keeps the unit from fouling.

If you hear other sounds, such as a “hissing” noise, call your water specialist as there may be a problem with the air gap or water pressure. 

Want a quote on an RO system and installation?

Your local authorized WaterTech dealer can give you a quote on a point-of-use reverse osmosis drinking water system for your home.

And right now, you can enter to win a FREE RO PureMAX II drinking water system simply by “LIKING” our Facebook page.

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  • I’ve heard about how reverse osmosis is a good way to filter water. I would like to have pure, drinkable water that doesn’t have fluoride, so it seems like a good idea to invest in a reverse osmosis water tank. It’s good to know that they’re quiet and that they only make a gurgling sound that isn’t very distracting. I didn’t know that they can be hooked up to a fridge. That’s really good to know. I’m sure that makes it a lot easier to access water in my home.

  • The water from our tap has a slight aftertaste that bothers my family. I love the idea of using a reverse osmosis filtration system on a fridge or ice maker. This sounds like a convenient way to get clean, great tasting water.

  • Can you please tell me if the PureMaxII uses any discharge water? If so, how much?.

    Also, Can I connect it directly to my kitchen sink, pot filler, island sink and ice maker or will the flow be too restrictive? I would ideally like RO water in all these locations.