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The check valve is a small but crucial component in the operation of a reverse osmosis system.
Without it, water can flow back into the reverse osmosis membrane from the storage tank, compromising the performance of the system and potentially causing serious problems.
There are two general approaches to installing a check valve in a reverse osmosis system. Here is a brief rundown of how that’s done.
So, how do you install a reverse osmosis check valve?
Installing a reverse osmosis check valve is pretty simple and straightforward.
As mentioned before, RO check valve location depends on its type.
Type A connects directly to the permeate port of your reverse osmosis membrane housing.
Type B sits inline, between RO membrane and automatic shutoff valve.
Modern home reverse osmosis systems utilize a number of additional valves in their operation. Typically you would also have a feed valve, automatic shutoff valve, and a flow restrictor.
The feed water valve simply connects your system to the water source in your home. Usually, you would have this hooked up directly to the cold water supply under your kitchen sink.
An automatic shutoff valve ensures that the system doesn’t work unnecessarily once the tank is full. Without an ASO valve, or when you have one but it’s operating improperly, your system will likely keep running all the time, even when the tank has been full for hours.
The flow restrictor connects to the drain line and limits the flow of water through it. Without a flow restrictor, most of the water that pushes against the membrane will simply flow out into the drain without getting filtered.#
It’s theoretically possible to use a reverse osmosis system in this manner, but it’s not really recommended because it will result in a lot of wasted water and reduce RO water quality.
An under sink reverse osmosis system is a comprehensive package for filtering household water. These systems typically work in multiple stages. First, you have a pre-filtration stage which gets rid of floating particles and chemicals like chlorine before water makes it into the reverse osmosis membrane. At that point, water is pushed against the membrane at a high level of pressure. As a result, almost only water molecules can make it through the reverse osmosis membrane.
Finally, filtered water is run through a post filtration stage to get rid of some additional contaminants like dissolved gases. At this stage, you might also add something like a remineralization filter to compensate for all of the minerals that got stripped out of the water during the reverse osmosis process.
If you have any questions about our RO check valve placement guide please don’t hesitate to leave a comment below!
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