Home Blog Buyer's Guides What Is A Reverse Osmosis Pressure Tank?

What Is A Reverse Osmosis Pressure Tank?

by Dr. Jonathan Doyle - Updated January 27, 2022
Although we have spent some time on our blog discussing Reverse Osmosis systems, and the details surrounding their use, we thought it may be pertinent to delve a bit deeper into additional aspects. One question we get quite often is: can an RO system be connected directly to a fridge? If this is you, let’s take a look at pressure tanks, and how they can serve as the perfect solution to your predicament.

What Is A Pressure Tank

An RO pressure tank serves as a water storage tank designed to fit underneath your sink, and work in-line with your existing Reverse Osmosis system. This add-on acts as a collection tank for any resulting purified water produced by your RO unit.
The Reverse Osmosis membrane acts as the core filtration membrane of your RO water purifier. Most of these membranes filter out contaminants as small as 0.0001 microns, including viruses, bacteria, heavy metals, organic compounds, and even radioactive substances. By removing these elements from your water source, you are poised to provide your family with safe, healthy drinking water. A pressure tank simply provides a storage tank to preserve this safe water for any length of time – even if you experience a loss of power.
We have all been there, enduring the slow speed at which an RO system produces filter the first glass of drinkable water. A pressure tank serves as a solution to sudden demand upon your Reverse Osmosis unit by enabling users to store purified water. This means, even when you aren’t actively using your RO system, it is still working to produce purified water for storage on your behalf.

How Do A Pressure Tank Work

In short, a pressure tank surrounds an internal inflatable air bag that makes up an RO pressure tank. As water enters into the bladder, the bladder is thereby squeezed to enable the inlet water to be subjected to pressure of the opposite direction. The pressure barrel is filled with water once the pressure equalizes to that of the inlet water pressure. It is at this point that the water inlet halts, as production is slowed to a complete stop. As users take water from the storage tank, by opening faucets, outward pressure is thereby collected to enable water to flow. As the water enters and exits the tank, a full cycle process is completed.

The Purpose Of A Pressure Tank

It is completely necessary to understand that regardless of the size of your pressure tank, it will have zero influence on the overall water production efficiency of your RO system. While it can improve the water intake efficiency in an effective manner, the buck stops there. The filtration of your water is controlled by a high pressure sensor or switch. Once the machine begins production, the water in storage flows out and causes an immediate drop in pressure.

Enables an RO System to Connect to Your Fridge

Because an RO system which lacks a storage pressure tank will need to run continuously throughout the day, it isn’t recommended that you connect it directly to a fridge or ice maker. This is simply because ice makers produce at a slow rate of which an RO system can easily outperform. This causes an RO machine to start and stop too frequently for proper operation, ultimately leading to the complete failure of said equipment. To combat this issue, the pressure tank was created to enable users to store filtered water for various appliances, including ice makers.

Shorten Waiting Time

One of the common problems you have probably faced with your RO system is the need to wat for water to be produced. An RO membrane takes more time to filter water due to the small size of the pores. This is necessary for the removal of tiny, seemingly insignificant contaminants – something an RO system is known for. A storage tank eliminates this issue, by storing filtered water for instant use at any time of the day.

Providing Extra Water Storage During Power Failures

Unfortunately, because an Reverse Osmosis system is completely reliant upon electricity to operate, it could leave you “stranded” in dire times. This means, in the event of a power outage, you will be unable to utilize your RO unit to produce filtered water for consumption. However, by installing a pressure tank, you are poised to store water for emergency use. In fact, some of these tanks provide portable functions that allow you to replace bottled purified water by taking out fresh purified water, instead.

Prolong Using Distance of RO system

When reverse osmosis is connected to appliances in long-distance, there would be pulse problems. The pressure tank perfectly resolves this problem by improving water flow with no decay. The suitable distance of PMT between tank and RO system is up to 16 feet.

Comparing A Waterdrop PMT To A Frizzlife Pressure Tank

Comparison Chart

Waterdrop PMT
Waterdrop PMT
Frizzlife MWT3
Frizzlife MWT3
  • Storage Capacity: 0.26 gallons
  • Material: High-Quality Food-Grade
  • Size:4.1” x 4.1” x 7.3”
  • Accessory Pack: Included
  • System Price: $29.99
  • Storage Capacity: 0.13 Gallon
  • Material: High-Quality Food-Grade
  • Size:4.5” x 4.5” x 8.3”
  • Accessory Pack: Sold Separately ($13.99)
  • System Price: $25.99 ($39.98 total)

Waterdrop Pressure Tank

Founded in 2015, Waterdrop has been devoted to providing reliable water purification solutions to solve water problems. After seven years of development, Waterdrop has gained a large number of loyal users in the United States. In the past seven years, we have attached great importance to the various needs of our customers for purified water, continuously improved product quality, and constantly developing new products. The latest pressure tank PT-PMT launched this time is our feedback on customers' needs.
The PMT is compatible with Waterdrop tankless reverse osmosis system: G3P800, G3, D6, G2P600, D4, G2MNR, G2. Check to see more undersink reverse osmosis.
In addition to the advantages of the RO pressure tank mentioned on the line, the PMT also has its own advantages. Thanks to the compact design, it is lager in capacity with smaller size. The storage capacity of Waterdrop PMT is twice that of frizzlife. Waterdrop has also considered the accessories of the PMT very intimately. As long as you buy our pressure tank, you do not have to buy the accessories separately, which is rather a bargain.