Best Water Separators for Air Compressors [2021 Buyer’s Guide]

| Last Updated: January 30, 2021

Tool Tango is reader-supported. When you buy through links on our site, we may earn an affiliate commission.

Rust can take a toll even on the best air compressors out there. And because there’s no way to compress air without getting water droplets, there’s no way to keep your air compressor in good working condition without a reliable water separator.

Don’t know what that is or how to choose one? Follow us in this buying guide, and you’ll get answers to questions you weren’t even aware you had!

Hoping to cut right to the chase? Below are the best best water separators for air compressors:

  1. Alpha Pure MS-0060-050NPT
  2. SMC AMG350C-N04BC
  3. Nanpu AC3010-03

Comparison of the Best Air Compressor Water Separators


Our Rating


Alpha Pure MS-0060-050NPT

  • 235 PSI
  • 60 CFM
  • Aluminum


  • 145 PSI

  • 53 CFM
  • Aluminum

Nanpu AC3010-03

  • 145 PSI
  • 70 CFM
  • Aluminum

Tailonz AC3010-03

  • 145 PSI
  • 70 CFM
  • Aluminum


  • 175 PSI
  • 106 CFM
  • Metal and Polymer

What is a Water Separator? 

Just like the name suggests, a water separator is a filter that collects and evicts the water that resulted during the air compression process. Its functioning principle implies putting even more pressure on the air.

The way that a water separator works leads to making the moisture from the air denser, all while keeping the air in a gaseous state. Denser moisture eventually turns into water droplets that are collected and evicted.

How to Choose the Best Air Compressor Filter Dryer 

Once you get to know how a water separator works, it will be much easier to spot and choose one of the best models. Performance-wise, you’ll want to check what pressure and what volume of air it can handle. Durability-wise, keep an eye on what’s it made of. 

Pressure Handling

Because these filters are all about compressing the air even more, pressure handling is an important indicator of their performance. Quality water separators will have a maximum pressure handling of 145 PSI to 235 PSI.


The volume of a water separator is also referred to as the size of the filter. It is typically measured in CFM and indicates the volume of air that the accessory can handle in the filtering process. Anything from 60 to 70 CFM is considered a good volume, though you’ll come around to values outside this range, too.


As far as the material is concerned, the water separator has a filter membrane that sits in a housing. This housing can be made of aluminum, steel, or a combination of metal and polymer. Typically, you’ll find them made of aluminum, though steel makes for a sturdier, and often way more expensive option that you may not necessarily need.

Review of the Best Air Compressor Water Separators 

Anxious to deep dive into some practical reviews of the best air compressor water separators? As always, we have a dependable selection lined up for you, starting from the best overall, all the way to an honorable mention. Here they are:

Best Overall:
Alpha Pure MS-0060-050NPT


  • Easy to install and use
  • Features a durable design
  • Requires low maintenance
  • Built for universal compatibility
  • Facilitates efficient liquid removal


  • Effective just for water removal, not oil
  • Adaptor for electric automatic drain must be purchased separately

Our Review:

Following our intensive testing, we’ve chosen the Alpha Pure MS-0060-050NPT as the best overall water separator. Its specifications truly speak for its performance – 1/2-inch NPT drain connection, 60 CFM volume, and a maximum of 235 PSI pressure handling make it a competitive model.

But there’s more to it than these numbers! The unit relies on centrifugal action to remove the water. It strikes a high rate of liquid removal. It has no element that would require extra care or replacement. And through it all, it isn’t just an effective separator, but also a low-maintenance one, meaning it’s a joy to rely on it!

What Makes This Product Stand Out?

Ready to pair with any air compressor model and tackle an outstanding maximum pressure, this Alpha Pure model truly makes the best choice. It’s also a low-maintenance water separator and the heavy-duty aluminum design vouches for its durability. All the more reasons to keep it on your shortlist.



  • Facilitates automatic drain
  • Handles a good air flow rate
  • Designed to work with existing air piping
  • Compliant with Restriction of Hazardous Substances
  • Also removes pollutants or other submicronic contaminants


  • Won’t filter dirt or oil from the water
  • Requires cooling the air before filtering it, for maximum efficiency

Our Review:

With the same 1/2-inch NPT connection like the best overall, the runner up shortly falls behind, volume-wise, with its 53 CFM. The maximum handled pressure is somewhat lower, at only 145 PSI, but it does come with an automatic drain and it supports the modular connection.

The water removal rate is impressive, as it can take out up to 99% of what gets into your air tank. And the fact that it is RHS-compliant will allow you to use it with even more confidence. To top it off, it doesn’t even cost that much, and the aluminum construction makes for a durable, therefore smart investment.

What Makes This Product Stand Out?

The second-best choice comes from SMC, and it doesn’t take much science to understand its strengths! You can easily tell it is well-built, and you can consider it a fairly heavy-duty model. You’ll install it in a jiffy. And anytime you want, you can flip its lid and check the water level through the sight glass.

Best for the Money:
Nanpu AC3010-03


  • Easy to install
  • Designed with a small profile
  • Features a solid metal housing
  • Budget-friendly water separator
  • Comes with a built-in wall mount system


  • Equipped with plastic fittings
  • Suitable mostly for home use

Our Review:

Ready to handle pressures of up to 145 PSI and with a 70 CFM volume, this filter from Nanpu is hard to overlook. As a budget-friendly option, it chooses high quality for the filter element, with a small compromise in the plastic fittings.

Even so, its filtering performances are at the top, and the brass filter predicts a longer lifespan, with the convenience of its reuse feasibility. Rest assured that the small profile encompasses a solid housing and just enjoy the fact that it comes with a wall-mount system in the package!

What Makes This Product Stand Out?

As always, our best-for-the-money selections stand out through the great value they provide, despite their low price tag. This Nanpu water separator for air compressors makes no exception and it will lure you with its outstanding filtering performance and the 5-micron brass filter. Needless to say, you wouldn’t expect to get these from such an affordable product.

Editor's Pick:
Tailonz AC3010-03


  • Affordable price point
  • Great operating pressure
  • More than decent flow rate at 90 PSI
  • Great deal for light-duty use around the house
  • Designed as a 3-in-1 oil air pressure regulator filter


  • Manual drain, not automatic
  • A tad smaller than you’d expect it to be

Our Review:

If you were used to only seeing plain water separators around here, embrace this Tailonz AC3010-03 as a 3-in-1 oil air pressure regulator filter! Our editors picked it for its valuable versatility, though you won’t help but notice how its specs are pretty high, too.

Apart from its functionality, it clearly aims to make your work more comfortable. Look at its transparent but durable, hard measuring cup, the backrest bracket built-in, or the precision pressure gauge. Yes, it’s small, but it provides great value, and it is built with quality and your convenience in mind.

What Makes This Product Stand Out?

It’s not often that you bump into such a water separator that adjusts the air pressure, filters both moisture and particles in the air, and does a wonderful job at lubricating the air passing through it. What’s more, it makes another affordable option, and it features the same aluminum body we only see in good-quality products!

Honorable Mention:


  • Low-cost water separator
  • Removes 95% of moisture
  • Equipped with polycarbonate bowl
  • Features a removable metal bowl guard
  • Simple functioning principle and operation


  • Plastic drain valve
  • Semi-automatic drain that works overnight

Our Review:

Yet another water separator for air compressors you’ll want to take a closer look at, this model comes from THB. Even though a combo of metal and polymer rather than the aluminum we were used to seeing, it does rely on an effective 5-micron filter.

Its maximum input and output pressure closely compete better-rated models, and its CFM flow rate is certainly something you haven’t seen before. Just keep in mind that it’s an airline water separator, use it as intended, and chances are you’ll be more than happy with its efficiency. 

What Makes This Product Stand Out?

This water separator traps particles, traps water, and drains water with an efficiency of up to 95%. What’s more, it does it all automatically, the moment pressure is released into the air hose. A semi-automatic drain by day, it turns into an overnight drain when you stop using it – pretty convenient, isn’t it?

Hold up, are you interested in other topics related to air compressors? If so, these might be something to check out: 

Aspects to Consider Before Buying 

We already went through the section of how to choose the best air compressor filter dryer, in the beginning of this buying guide. So, you must know, by now, that it takes looking into a separator’s pressure handling, volume, and material before making a choice. However, consider the following two essential aspects, too:

Required Maintenance

Good maintenance will spare you from costly repairs and downtimes. Maintenance-free is the best you can get. And the water filters with no elements you’d have to replace will make the most convenient choice.


Nobody wants to pay for a water separator only to discover that it is incompatible with the air compressor it was bought for. To avoid such situations, always make sure that your chosen model clearly states universal compatibility.

Cautious Considerations to Keep in Mind 

Their practicality left aside, there are still things you’d want to consider before making up your mind for a particular model. For once, you’d have to keep the following cautious considerations in mind:

Typically, Not An Oil Or Dirt Separator

Just like the name suggests, a water separator will focus on filtering the air and eliminating moisture. While there are some models out there equipped to also filter oil or dirt, this isn’t the norm, and you should set your expectations accordingly.

You Might Want To Add A Drain Hose

The best water separators come with an auto drain function. Still, you might find yourself wanting to add a drain hose to the eviction valve. It’s a process that typically involves coupling a 1/8 push lock fitting with the drain valve. Always ask the manufacturer before you proceed to such upgrades.

How to Install a Water Separator on an Air Compressor 

A water separator is a simple accessory. If you pick one with minimal maintenance, using it will be a breeze. And so is the installation, provided you know how to go about it! Most people would jump to mounting the filter next to the comp. But this is actually the wrong way to do it!

If you want to make the best of your water separator, you’ll have to make sure it sits at least 20 ft away from the air compressor. The closer it sits to the compressor, the warmer the air will be when it enters the filter.

Heated air picks up moisture, and trying to filter it while still warm is ineffective. When you install the separator 20 ft away from the compressor head, you’re giving the air enough time to return to the ambient air temp. Thus, much of the moisture will condense in the process and make the water filtering truly effective.

As for the actual installation, you should:

  • Begin by carefully reading the user guide manual, where you’ll find all the necessary details – these details might vary from one model to another, so don’t assume you know what you need to do, but rather refer to the instruction manual first.

  • Make sure you find a place that is far enough from the air compressor, as suggested above, and that will also allow you to keep the water separator in a vertical position.

  • Always check the housing of the water separator, for the arrow that shows you which is the air flow direction – this will indicate you the correct position for mounting the filter.

  • Always clean the lubricated threads of the filter body before the actual installation.

  • Take the time to check the body of the filter and make sure it’s perfectly fastened and that all the parts under pressure are in good condition.


Water separators are not that complicated, though you’ll still want to take the time and learn their basics. It will help you pick a reliable model that doesn’t cost you too much, and teach you how to install it in order to make the best of this small but handy air compressor accessory.

People Also Ask

On your way to shop for the best water separator for air compressor? If you still have questions, we reckon you’re thinking about the following aspects:

Are Water Separators Hard to Install?

Water separators are not hard to install. The best models are shipped with instructions in the package. And as shown in the above section of How To Install A Water Separator On An Air Compressor, they typically have some arrows imprinted on them, for guidance. When in doubt, check the instructions sheet or hop online to google for your exact type of water separator.

What is the Difference Between a Filter Dryer and Water Separator?

A water separator is a filter in itself, with capabilities limited to filtering, trapping, and evacuating moisture as plain water. In contrast, a filter dryer is a more complex, often 3-in-1 filtering mechanism that includes a water separator along with an oil and dirt filter.