How to drain air compressor [2 proven easy methods]

Every workshop needs an air compressor. You can use it to power pneumatic tools like impact wrenches, brad nailers, ratchet wrenches, etc. You can also use it to inflate soccer balls and many more items. 

A compressor with a tank allows you to store compressed air for future use. But when the compressor is not in use, there’s a need to drain the tank to reduce the moisture inside the compressor tank. Water condensation on the tank can cause damage to electrical components and also reduce its working life. However, this is a task not many people know how to do properly.

It is not a very difficult task to drain an air compressor. This article tells you how to drain an air compressor, I will try to make the process as quick and simple as possible.

How to drain air compressor

How to drain air compressor guide

There are two methods for draining the air compressor tank. The first one is Manual Drain. The other one is Automatic Drain. Let’s take a look at each individual.

Method 1: Manual process 

Step 1: Turn off the air compressor.

Before you drain the tank, the first step is to turn off the compressor. It ensures that water will not accumulate inside the air tank due to extra pressure.

Step 2: Locate the Drain Valve

Every air compressor is different, so you need to determine where the drain valve is located on your air compressor. The drain valve is generally located at the bottom of your tank, right where it meets the base. It is located there because it is the easiest place to drain. In a few rare instances, it can be on the side.

Step 3: Open the drain valve to let water out

Now that you have found where the drain valve is, the next step is to open it. Turn the valve slowly and make sure it is open. But be careful of the sudden excess of water coming out of it. This may not be much, but you will have to be careful.

Step 4: Close the drain valve

This part is easy because you just have to twist it from open to close position, and that’s it. Experts recommend using thread tape when closing the drain valve. It will ensure the valve is not going to leak in the future. 

How can you check the leaks?

It is easy to check for tank leaks. Just pour a little bit of soapy water on the tank and check out for bubbles. If you see bubbles, it means there is a leak on the tank. If the leak is detected, simply tighten the screws on the drain valve and check again.

Method 2: Automatically draining an air compressor

If you don’t want to drain the compressor tank manually, you can use an automatic drain valve. This will let the air compressor tank be drained automatically by setting a time for it. 

An automatic drain valve is one of the inventions in the compressor world. It’s great because it allows you to automatically set a schedule for your air compressor to open and drain the water from your tank. 

But the question is here How to set Automatic Drain Valve? 

Well, it’s pretty simple. Follow the below steps to set it.

Step 1: Find out Where Your Automatic Drain Valve Is Located

Just like how it’s done in the manual process, make sure you know where your automatic drain valve is located. Just like in the manual process, this valve is located at the bottom of your tank.

Step 2: Set Your Schedule For Draining 

You need to set the amount of time you want the air compressor to drain water. For example, you can set it to be done once a week or daily.

Step 3: That’s It

Once you have set the schedule, it is time to let your air compressor do its job. The tank will drain itself according to the schedule you have set.

Some basic guidelines to follow while draining the compressor tank

  • Unplug The Compressor

You will have to ensure that the air compressor is turned off before draining the water.

  • Wear safety goggles

When draining the tank, your eyes will be close to the drain valve. So make sure you wear safety goggles to avoid any injury or accidents.

  • Plan The Draining Time

Make sure you plan the time for draining because it will take some time. You don’t need to rush while doing the process.

  • Check leaks

Pour a few drops of soapy water on the tank and check if there is any leaks. If you find any, tighten the screws of the drain valve.

What Happens If I Don’t Drain My Air Compressor.

If you don’t drain your air compressor, it can cause many problems. For example, the water left inside the tank will create a lot of pressure and lead to a broken tank. Besides this problem, there are also other conditions that can occur. Other conditions that may be caused by not draining your tank are rust and corrosion.

If the tank is not drained for a long time, there will be a build of rust and corrosion inside the tank. This can result in a very messy surprise when you open up your air compressor for some work.

Remember, draining your tank is very important and should not be neglected. Just because you don’t use the compressor for a long time doesn’t mean you can neglect this process.


Draining the water from your air compressor tank is not hard to do. You need to know where the drain valve is and set a schedule for the air compressor to drain water automatically. 

This is much better than draining it manually when you are done using it. Remember, you don’t want water left inside your tank. It can cause a lot of problems with rust and corrosion. You also need to know that not draining your tank for a long time can cause an even bigger problem. 

So, make sure you drain the water from your tank every time after use. This way, your air compressor remains safe. 

I hope this article about how to drain an air compressor is helpful for you. If you have any questions about draining the air compressor tank, feel free to contact us. 


How often do I need to drain my air compressor? 

A good rule of thumb is to drain the tank after every day’s usage. This will prevent moisture from building up inside your compressor.

How do air compressor drain valves work?

The drain valve allows all of the tank’s contents to empty into an external container when it is opened.  
The drain valve is typically located near the outlet connection on the bottom of most air compressor tanks. 

Why is it important to drain the compressor tank?

You must drain your tank after each use. Moisture can cause rust and corrosion inside the tank. This will decrease the life of your air compressor.

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