Maintaining Your Compressed Air System

A poorly maintained compressed air system wastes energy, increases operational costs, and risks unexpected failures. Common issues include leaks, pressure loss, contamination (like moisture or oil). Studies suggest that up to 30% of compressed air is lost to leaks in an average system, while contaminants can damage downstream equipment or spoil products. Routine maintenance tackles these problems head-on, ensuring reliability and cost-effectiveness.

Key Maintenance Practices

  1. Monitor and Replace Intake Filters
    The air compressor draws in ambient air, which is often laden with dust, dirt, and water vapor. The intake filter is your first line of defense, protecting the compressor’s internals from wear. Over time, debris buildup increases pressure drop, forcing the compressor to work harder and reducing efficiency. Check the filter regularly—typically monthly—and replace it when the pressure differential exceeds the manufacturer’s recommended limit (often around 5-10 psid) or at least annually.
  2. Manage Moisture with Dryers and Drains
    Water vapor in compressed air condenses as it cools, leading to rust in pipes, damage to pneumatic tools, and quality issues in applications like painting or food processing. A dryer—whether refrigerated, desiccant, or membrane—is crucial. For smaller systems or point-of-use applications, inspect and clean dryer coils or replace desiccants as per the manual (usually every 1–2 years). Automatic drain traps should also be checked quarterly to ensure they’re removing condensate effectively.
  3. Audit for Leaks
    Leaks are silent efficiency killers. Even a small 1/8-inch hole at 100 psig can cost over $1,000 annually in wasted energy. Conduct a leak audit every 6–12 months using an ultrasonic leak detector. Focus on fittings, valves, and older piping sections, where vibration or corrosion often takes a toll. Repairing leaks promptly can save 20-30% on energy costs. EXAIR’s 9207 can help with this task.
  4. Optimize Pressure Settings
    Over-pressurizing the system to compensate for downstream losses wastes energy—every 2 psig increase adds about 1% to power consumption. Use pressure regulators at the point of use to deliver only what’s needed. Monitor system pressure monthly to ensure it aligns with demand, adjusting as equipment or processes change.

How EXAIR Products Enhance Maintenance and Efficiency

EXAIR’s Intelligent Compressed Air Products are engineered to complement these maintenance practices. Here’s how some specific items can help:

  • Ultrasonic Leak Detector (Model 9207)
    Pinpointing leaks in a noisy compressor room can feel like finding a needle in a haystack. EXAIR’s Ultrasonic Leak Detector uses sound wave detection to identify leaks with precision, even in high-decibel environments. Regular use during audits—say, every 6 months—helps maintenance teams catch and fix leaks early, slashing energy waste. Its portability and ease of use make it a must-have for proactive upkeep.
  • Automatic Drain Filter Separators
    Moisture and particulates in the air stream can clog tools or ruin products. EXAIR’s Automatic Drain Filter Separators (available in various port sizes, e.g., 1/4″ to 1-1/2″ NPT) feature a 5-micron filter and centrifugal separation to remove bulk liquids and debris. The auto-drain feature expels collected water without manual intervention, reducing maintenance time. Replace the filter element annually or when the pressure drop hits 10 psid to keep air quality high and downstream equipment safe.
  • Oil Removal Filter
    For applications requiring ultra-clean air—like electronics assembly or pharmaceutical production—the Oil Removal Filter takes filtration further. With a 0.03-micron coalescing element, it traps oil vapor and fine particles, coalescing liquids for gravity drainage. Pair it with a Filter Separator for a two-stage approach, and replace elements yearly to maintain performance. This ensures sensitive equipment stays contaminant-free with minimal upkeep.
  • Pressure Regulators
    Excessive pressure at the point of use is a common efficiency drain. EXAIR’s Pressure Regulators (included in many product kits) let you dial in the exact pressure needed—e.g., dropping from 100 psig to 80 psig can cut air usage by nearly 20%. Install them downstream of filters for accurate control, and check settings quarterly to match evolving process demands. They’re a simple, maintenance-free way to optimize demand-side efficiency.

A well-maintained compressed air system isn’t just about avoiding breakdowns—it’s about maximizing efficiency and minimizing costs. By pairing routine checks with EXAIR’s engineered solutions, you can tackle leaks, contamination, and over-pressurization head-on. The result? A system that runs smoother, lasts longer, and keeps your energy bill in check. Whether you’re blowing off parts, powering tools, or cooling processes, these strategies and tools ensure your compressed air works as hard as you do.

For more insights or help selecting the right EXAIR products for your system, reach out to an Application Engineer. Let’s keep your air flowing intelligently!

Jordan Shouse
Application Engineer

Send me an Email
Find us on the Web 
Like us on Facebook
Twitter: @EXAIR_JS

Types of Filters Used in a Compressed Air System

Most of EXAIR’s line of Intelligent Compressed Air Products have no moving parts and require no maintenance. The caveat to the “no maintenance” aspect is proper filtration at the point of use. Many products have very tight orifices that could get clogged from any contaminants such as particulate, condensate, and lubricant. EXAIR recommends point of use filtration to be installed just upstream of any EXAIR Product for this purpose.

There are three primary types of compressed air filters: particulate, coalescing, and adsorption. Each have their own inherent characteristics and can be used in conjunction with one another. Each style is used to handle a different form of contaminant that’s present within the distribution system of your compressed air supply.

9001
EXAIR Model 9001 Auto-Drain Filter

Particulate filters – Particulate filters are available with different filtering mechanisms that allow you to control the particulate size that will be filtered out. The higher the level of filtration, the greater the pressure drop you’ll experience at the outlet of the filter. Styles are also available with either a polycarbonate bowl or metal bowls, depending on the application and environment.

Any filter with a polycarbonate bowl should have a metal guard on the outside to provide protection for personnel should a failure occur. In these styles of filters, compressed air is forced through a filter element that blocks any particulate contained within the air supply.

These filter elements are generally a sintered bronze material with filtration levels from 40-5 micron possible. Over time, the filter elements can clog and increase the pressure drop at the discharge of the filter. They’re relatively inexpensive and should be replaced yearly to maintain optimum performance and mitigate pressure drop. They also remove liquid drops as well from the air supply, containing them within the bowl. Styles with both manual-drains and automatic-drains are available that will drain the bowl of excess moisture automatically through the bottom of the filter.

9005
EXAIR Model 9005 Oil Removal Filter

Coalescing Filters – The coalescing filter is used to remove very fine water vapor as well as any residual oil. These filters are highly recommended to be installed just prior to any dryer that contains a media that would be compromised by any lubricant passing through it. Coalescing filters utilize an element typically made up of glass fibers that “coalesce”, or combine, the fine water vapor and oil aerosols until the droplet size becomes large enough that it drops off into the bowl or filter housing. With a coalescing filter, the most common cause of pressure drop increase is due to particulate clogging the filter element. Because of this, a particulate filter should always be installed just prior to any coalescing filters.

Adsorption Filters – The final type of compressed air filter is the adsorption filter. Where the particulate filters can remove the majority of contaminants and the coalescing filters the residual oil, they are not capable of removing lubricant vapors or oil. That’s where the adsorption filter comes in. In addition to removing the finest oil vapors, they also can eliminate odors from the compressed air supply. The oil vapors and odors adhere to activated carbon within the filter, removing them from the air supply. These filters are commonly found within the food processing industry, where any contaminants in the air supply could impact the integrity of the product.

EXAIR has a line of Automatic Drain Filter Separators and Oil Removal Filters, available from stock, to make sure the quality of your air supply is sufficient for proper operation of any EXAIR product. Feel free to give us a call and any of our Application Engineers will be happy to assist you.

Tyler Daniel
Application Engineer
E-mail: TylerDaniel@EXAIR.com
X: @EXAIR_TD

Dew Point and Water in Compressed Air: Understanding the Effects

In systems, it is important to understand the type of medium that is being used.  For most EXAIR products, this will be compressed air.  As the air compressor draws in ambient air, it also brings in dust, contamination, and moisture into the system.  If untreated, the pneumatic system will have to contend with these foreign “invaders” that will affect the performance of your pneumatic devices.  One of the most common problems is water.

Water enters the compressed air system from the water vapor already present in the ambient air, which is referred to as the dew point or relative humidity.  When you take ambient air and compress it, the amount of “elbow room” for the water vapor decreases.  This causes the water vapor to condense and create liquid water.  It would be similar to a water-soaked sponge.   As you compress it with your hands, the sponge will not be able to hold on to the water.  Similarly, as the air is compressed, water will start to form and fall out into the compressed air system.  Water is a by-product of a compressed air system.

Visual depiction of the impact of water vapor contained amongst air particles and how this reduces available volume during compression.

The definition for determining if liquid water is present in your system is called the pressure dew point.  Dew point is the temperature at which water vapor will condense and form water droplets.  If the dew point temperature and the air temperature are equal, then the air is considered 100% saturated (water vapor will start to condense to form water droplets).  In compressed air systems, air dryers are used to reduce the dew point temperature.  This means that unless the ambient temperature falls below the dew point temperature, water vapor will not condense into a liquid state.

There are two major types of compressed air dryers; refrigerated and desiccant.  The refrigerated air dryers are the most common, and the dew point is measured at about 39oF (4oC).  So, unless the air temperature gets close to freezing, i.e., the piping system that goes outside in cold weather, water should not be present.  Desiccant air dryers can achieve dew points as low as -40oF (-40oC).  This compressed air is very dry and can be used for medical systems, food and beverage processing, and instrument air.  The reason is that bacteria cannot survive in compressed air that is that dry.  The other types are dewpoint reducing systems, which include membrane and deliquescent dryers. 

Good engineering practice calls for point of use filtration and moisture removal, such as that provided by EXAIR Filter Separators.

For most pneumatic devices, a Filter Separator with an auto-drain should be used as a minimum amount of protection.  Even with systems that have compressed air dryers as described above, they are mechanical devices.  So, failures can occur.  You should review your compressed air system to ensure that your pneumatic system, including EXAIR products, is operating at peak efficiency.  This will include your supply system, compressed air leaks, and blow-off devices. 

Moisture-laden compressed air can cause issues such as increased wear on the pneumatic tools, the formation of rust in piping and equipment, quality defects in painting processes, and frozen pipes in colder climates.  Regardless of what products you’re using at the point-of-use, a compressed air dryer is undoubtedly a critical component of the compressed air system.  Providing clean, dry air to EXAIR Products or other pneumatic devices will help to extend the life of your equipment.  If you wish to discuss more about your compressed air system or how EXAIR can provide a more efficient way to use that compressed air, an Application Engineer will be happy to assist you.

John Ball
International Application Engineer


Email: johnball@exair.com
Twitter: @EXAIR_jb

Why – And Where – Do You Need Filtration In Your Compressed Air System?

Good engineering practice, and proper system design, call for filters at various points in a compressed air system. I’m going to go through these along the path that compressed air follows, from being drawn from atmospheric pressure in to the compressor, to being returned to atmospheric pressure at its point of use.

Any air compressor is going to have an intake filter. The small “pancake” compressor in my garage has a little disc looking thing with a screen whose mesh is about the same as my house’s window screens. Larger industrial air compressors have cartridge-type filters that impart a spiral motion to the incoming air. That motion actually removes most of the incoming particulate, while the rest gets caught in the pleats of the fiber element. The main purpose for an intake filter is to protect the compressor’s internal components. Solid particulates can really do a number on the high speed, close tolerance moving parts inside a compressor, in a hurry.

All the other filters you might find are there to ensure proper operation of the rest of your compressed air system:

  • Distribution. No intake filter is going to be 100% efficient, nor will it remove especially fine particulate that doesn’t present a real risk of damage or wear to the compressor. Intake filters also will not remove oil (or oil vapor) and water (or water vapor). The compressor itself can actually add contaminants to the compressed air, in the form of wear particles (remember those close tolerance moving parts I mentioned above?) and oil carryover. All of these contaminants will, however, be detrimental to the pipe & fittings that takes the newly compressed air to where it’s used. They can cause a buildup on the inner walls of the piping that inhibits flow. Water causes the pipe to start rusting from the inside out. When that rust scale breaks loose, it can clog, foul, or damage valves, fittings, and other control devices in the distribution header. Ideally, you’ll use filtration with a particulate element, a centrifugal element for water, and a coalescing element for oil/oil vapor (if needed…this isn’t a concern for oil-free compressors, for example).
  • Distribution, part 2. If your facility is large enough, you may need filtration at strategic locations…perhaps one for the air going to the machine shop, another for an area with machinery equipped with pneumatic cylinders, another for an assembly area where pneumatic tools are used, etc. The type(s) of filter(s) you use at those points will be determined by what the air is used for. If you know you have oil carryover from your compressor, you probably want a coalescing filter on the line to Safety Air Guns that blow off parts before painting. You don’t need them on lines going to your pneumatic tools, though…that carryover will likely help supplement the point-of-use lubricators that they use.
  • Point-of-use. Good engineering practice calls for a final stage of filtration, located as close as practical to the air operated device(s). EXAIR includes a Filter Separator with a 5 micron particulate element and a centrifugal element for water with all of our product Kits. Oil Removal Filters are also available for oil/oil vapor. They also provide additional particulate filtration to 0.03 microns.
EXAIR offers a variety of Filter Separators (left), Oil Removal Filters (middle), and Pressure Regulators (right) that are suitable for a wide range of point-of-use compressed air applications. Contact an Application Engineer for more details.

At EXAIR, we’re here to make sure you get the most out of your compressed air system. If you’d like to find out more about filtration…or any other aspect of air treatment (drying, regulating, cooling, etc.)…give me a call.

Russ Bowman, CCASS

Application Engineer
Visit us on the Web
Follow me on Twitter
Like us on Facebook