FAQs on RO Systems

What is Reverse Osmosis. The process of reverse osmosis, is defined as, the forcing of water under pressure through a semi-permeable membrane. That sounds real technical so I’ll explain it in lay-men’s terms. When you look at a membrane housing, you will see that there are two tubes coming out of one end and only one entering at the other end. The water enters the end with one tube. And for ex-planation purposes, if you were looking down the center of a pipe or membrane housing, you can imagine it divided down the center by a material much like plastic wrap you would use in your kitchen at home. Picture the water coming in on one side of this material and all the way at the other end, on that same side, there is a line to the drain. This is where all the contaminants are flushed out. On this line is a drain line flow control which is matched to the membrane. This chokes off the flow, just ever so slightly, creating the proper amount of back-pressure forcing the proper amount of the water through this material. Only the purest water can get through. All the way at the other end, on the other side of this material is the line to the storage tank where this pure water is stored until you need the water. This line does have a check valve on it to prevent back-pressure against the membrane. When you call for water at the RO faucet, water leaves this storage tank and proceeds to the post filter where it is polished to remove any objectionable taste and odors that may have gotten that far giving you great tasting water for your uses.

How often should I change my RO filters? A good rule of thumb is to change them every year. In areas where the tap water gets hot during the summer months, you should consider changing them every six months, spring and fall usually or just in the fall for winter visitors. The reason for this is that 84°F is ideal temperature for bacteria growth. The city should include chlorine that should kills this bacteria in a perfect world. In areas like Las Vegas or Phoenix the tap water reaches the mid 80°F all summer long. This recommendation is based on having relatively clean city water supply. If you have a private well, you may have a dirtier water supply and this may plug the sediment pre-filter, requiring it to be changed more frequently.

How does a reverse osmosis system work? The system is a combination of different filters together forming the reverse osmosis system. The first filter is a five micron sediment filter. Five micron is an extremely fine filter. To put it in perspective, a human hair is 50-60 microns in size. The smallest you should be able to see with the human eye is 30 microns. That would be like a fleck of dust floating in the air. As you can see, five microns is a fine filter. The next filter or two are some type of carbon, either granular activated carbon(GAC) or a carbon block filter(CBC) or some combination thereof. This filter would remove all of the chlorine and any existing organic contaminants. The membrane is not able to handle large amounts of either of these. Next would be the membrane which was explained in detail above in the first question. The next filter is usually the post filter and is there as a polisher to catch any objectionable taste and odors that may have gotten that far giving you great tasting water for your uses.

If I don’t use my system much, will I still need to change my filters? Not using the system is the worst way to use your system. Do not horde your water. Use it for your house plants, pets, steam irons, any kind of steamer, etc. The more water you use the better the water will be and the better the system will work. You cannot waste water. Water goes nowhere other than recycling right back to earth. You can have other factors like extremely high water bills, a drought or a logistics problem like being thirsty in Death Valley. But typically you cannot waste water. By not using your system, you are allowing the water to set stagnant, thereby letting bacteria to grow everywhere. If you use your system very little, you should let it run dry, preferably at bedtime once a month, and then turn it off before retiring to bed. This will allow you to wake to a full tank of fresh water. And yes, you will still need to change your filters.

Why do I get very little water out of my system? This problem could be caused by any of many problems. The sediment filter could need to be changed. You may be very overdue to change all your filters. Your water pressure could be too low for the system to function properly. This is very rare but possible. Your membrane may be bad. Your storage tank could be bad. You may just need to add air to the storage tank. This should have a pressure of 8-10 psi when the faucet is on and the tank is empty.

Why do I have hollow ice cubes? This typically means the icemaker is not getting enough water delivered to it. This could be any of the problems mentioned above.

How much pressure should I get at the RO faucet and the refrigerator? The typical water pressure is about half of the your tap water pressure. Water at the refrigerator can be affected by the way your refrigerator is piped. Some refrigerators only have a coil of tubing in a cold part of the refrigerator to cool your water. Most refrigerator manuals say to not use with an RO. This is false and there to save them service on their units. We have over the years hook thousands of reverse osmosis systems to refrigerators without problems.

How long should my membrane last? Membranes should be replaced when they test bad or reach a point where the rejection is below 75% of the Total Dissolved Solids. This could happen in as little as two years or they could last as long as 13-14 years or longer. You can tell by your ice if the system is hooked to the refrigerator. Your ice will be relatively clear if your membrane is good and your ice will turn very cloudy with a bad membrane meaning that it should be replaced.

Will this make the water taste better? Taste is a very personal thing and your taste may vary greatly for the next person. In the dictionary, water is described as a colorless, odorless, tasteless liquid. That is how water should be and your taste will determine whether or not you like it or not. Having someone not like RO water is a very rare occurrence. Typically, once you get used to drinking RO water, you will almost never touch the glass of water put on the table by the waitress again.