How to Drain an Air Compressor?

How to Drain an Air Compressor?

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There are many questions regarding the proper maintenance of an air compressor and how to drain it makes it to the top of the list.

This article is all about the importance of draining your air compressor, how to do it, why you should do it, and how often.

There are two ways through which you can drain your air compressor: Manually or automatically.


1. Draining an Air Compressor Manually

Step 1: Locating the Drain Valve

More often than not, you’ll find the drain valve at the bottom of the tank whatever the design of your air compressor is.

In some cases, you’ll find the valve on the side of the tank. In such a case, the water can be drained out by the air pressure to make the process easier.

However, this design has several disadvantages and the main one is that you can’t drain your tank if there isn’t enough pressure inside.

Another problem is that the valve can get clogged up with rust over time.

But admittedly, this design makes the valve easier to open and close.


Step 2: Opening the Drain Valve and Getting Rid of All the Water and Sludge

After you’ve opened the drain valve by rotating the ring in an anti-clockwise direction, all the water that’s inside will start pouring out under the effect of gravity. Of course, that’s in the case the valve is located at the bottom of the tank.

If the valve is located on the side, you’ll need some pressure inside the tank. If you don’t have that, you should start the compressor to get some pressure and then stop it before opening the valve.

The pressure you induce will push the water out from the tank.

Make sure you have a bucket at the bottom o the drain valve so that you don’t flood your floor with water and rust residuals.

It’s also recommended that you wear gloves during the process.

Make sure that you open the valve fully. Sometimes opening it partially creates a little passage that the sludge blocks, making bubbles come out as if your tank has been drained when in fact, it still contains some water.


Step 3: Close the Drain Valve and Double Check for Leaking

After you’re done with draining the water and the sludge from the tank, close the valve carefully.

If you’ve removed the whole drain valve, use new thread tape over it to stop it from leaking when you reinstall it in the compressor.

You can use a soap bubble to detect any kind of leaking.

After running the compressor to build some pressure, cover the drain valve with a soap bubble. If any bubbles pop, that means you leak.

In that case, tighten it even more securely using a wrench.

If it still leaks, uses more thread tape over the drain valve.

2. Draining an Air Compressor Automatically

If you don’t want to bother draining your compressor’s tank manually, attach an electronic automatic drain valve.

You can set the timer with a specific time duration according to the frequency of your operation.

These automatic valves are powered by a 12V wall source and can be wired with the control system to monitor the function.

To install an automatic drain valve, screw out the manual one and replace it with the automatic one. After that, you can simply plug it into a wall socket to power it up.

Setting a Timer on an Automatic Drain Valve

There’s a knob that you can turn to cycle the device for draining and set the timer. You can calibrate it for hours or days –though daily drainage is the recommended option.

What’s the Importance of the Drain Valve on an Air Compressor?

Any air compressor will have a small water drain to get rid of any moisture that accumulates inside the tank due to the effect of pressurizing the air.

Where Does the Water Come From?

The pressure inside your air compressor causes the vapor coming in with the moisture of atmospheric air to condense and form water droplets inside the compressor’s tank.

The longer the air compressor runs, the more moisture is accumulated.


How Often Should You Drain an Air Compressor?

Air tanks should regularly be drained to maximize their efficiency and durability.

But exactly how often you should drain them depends on the intensity of your use.

If you run your air compressor continuously for hours throughout the day, then you’d have to drain the tank multiple times per day.

However, if your use isn’t that intense, then you should drain it after you’re done using it. Around once per day would be good enough for mild use.