Help, My RO Tank Won’t Fully Empty!

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Whether it be disassembling your reverse osmosis system for transport or checking the psi of your empty RO tank, there may be occasions where you want the tank completely empty.

To do this, you need to do a little more than just open the valve and let the water flow out.

Follow these steps to empty your RO water tank completely!

Key Takeaways

  • It is perfectly normal for an RO tank to not fully empty.
  • This is because, as water flows out of the tank, the air pressure inside decreases. At a certain point the internal tank pressure won’t suffice to push out any more water.
  • If you want to completely empty your reverse osmosis tank, you will need to pump air inside.

Help, My RO Tank Won’t Fully Empty!

First things first, don’t freak out! It is perfectly normal for an RO tank not to empty completely. The amount of water that is pushed out depends on the air pressure inside the tank. As water leaves the storage tank, the air pressure decreases, reducing the water flow until, eventually, no more water will come out.

This is why, when emptying an RO tank to measure the psi, you need to use a bicycle pump or compressor to get that last bit of water out.

How to Fully Empty a Reverse Osmosis Storage Tank

To completely empty your RO storage tank, you need to follow these steps:

Under Sink Reverse Osmosis System

What You’ll Need

  1. Bicycle tire pump or compressor
  2. Pressure gauge

Step by Step Instructions

1. Shut off the RO Water Supply

Turn off the water supply to the RO system, and close the storage tank water valve. Open the RO faucet to drain the remaining water.

2. Remove the RO Storage Tank

Disconnect the storage tank from the rest of the RO system, and take it to a place that can get wet. Usually, the garden.

3. Empty the RO Storage Tank

Open the tank valve and let the water flow out until it gets down to a trickle.

4. Pump Out the Remaining Water

Get your bicycle pump or compressor, and use it to pump the last bit of water out of the tank.

If you are emptying the tank for the purpose of checking the air pressure in it, then you need to follow these additional steps:

5. Measure the Empty Tank Pressure

Measure the tank psi with your pressure gauge, and depressurize or repressurize if needed to a psi of between 6-8.

6. Reconnect the Tank to the RO Unit

Once the tank is at optimal pressure, reconnect it to the RO system.

If you have any questions about what to do when your RO tank won’t fully empty please don’t hesitate to leave a comment below!

About the Author Alexandra Uta

Alex is a content writer with an affinity for research and a methodical attention to detail. Since 2020, she has fully immersed herself into the home water treatment industry only to become an expert herself. Alex has been using water filters and similar products for years which has gained her lots of hands-on experience.
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