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Choosing the Right Compressed Air System for Your Facility | DIRECTAIR®

Written by DIRECTAIR® Insights Team | Dec 11, 2025 12:00:00 PM

Choosing the correct industrial air compressor size and system starts with more than just “a number.” It’s about understanding actual compressed air CFM and PSI demand, how often equipment runs, what varies by shift, how clean the air must be and where your facility is headed next quarter, next year, and 3–5 years in the future.

In this guide, you’ll learn how to size by demand (CFM / PSI), profile load patterns, match architecture (fixed/VSD/networked) to your variability, avoid over- / under-sizing, and how to factor in air quality, storage, dryers, filtration, and piping.

Need assistance determining the right sized compressed air system? Contact DIRECTAIR® today to meet with a compressed air expert.

Typical Air System Ranges by Facility Size

While every facility should determine their air compressor size by measured demand, most plants fall into these categories:

While the above are good guidelines, your actual system size should be based on duty cycle, baseline vs. peak, and air quality requirements, not just equipment.

DIRECTAIR® provides compressed air as a utility, with different levels of service based on your CFM usage. Air as a utility is a great way to cut costs, become energy efficient, and keep clean, reliable air at the forefront of your operations.

Step 1: Quantify Air Demand (CFM) and Pressure (PSI)

When trying to determine “what size air compressor do I need”, you need to quantify the loads driving the system. Start by building a demand list.

For every air-using tool or process, identify:

  • Required compressed air CFM
  • Required compressed air PSI
  • Duty cycle
  • How many compressors run at the same time
  • Possible future additions or seasonal spikes

It is best practice to log your data and do a compressed air audit, if possible. This is the most accurate way to get an average vs. peak demand profile. It prevents sizing air compressor systems based on inflated “worst case scenario” values.

Oversizing a big air compressor increases costs due to too much energy being used. Undersizing causes downtime by not having enough power to operate. Baseline and peak demand are crucial to finding the best size air compressor for your operations.

DIRECTIAR® can help you determine the right air system by testing your current system.

How to Conduct a Compressed Air Audit

A compressed air audit uses data loggers on your existing air system to track flow (CFM), pressure (PSI), duty cycle, and cycling behavior over time, which is usually 7+ days to capture real shift patterns.

To start your own compressed air audit:

  1. Open an Excel Worksheet on your computer and input the following headers into the columns: Equipment, Qty, CFM, PSI, Duty %, Simultaneity, Notes.
  2. List each piece of equipment you have, for example CNC, Packaging, Tools ,etc. Document the quantity and all the elements above.
  3. Log your activity for 7+ days to capture patterns.
  4. After the end of your 7+ days, calculate the Average CFM and the Peak CFM.

Once you have estimated average demand and peaks, plot the pattern. Look at:

  • Baseline operations
  • Peak burst events
  • Shift patterns

This will determine whether a fixed-speed, variable speed drive (VSD), or multiple networked compressors make the most sense.

If you need a more formal air audit or have additional questions, book a meeting with a DIRECTAIR® expert to get started.

Step 2: Match Compressor Types to Your Load

Different load patterns call for different compressor configurations. Once you have your load profile (baseline vs. peaks), choose the system type that best aligns with how your plant actually uses the air.

Fixed-Speed Compressor

  • Best when demand is steady or predictable all day
  • Good fit for stable, continuous operations
  • Lowest initial capital cost

Variable Speed Drive (VSD) Compressor

  • Ideal when demand swings up and down during shifts
  • Adjusts output to match real-time CFM needs
  • Often produces the biggest energy savings in variable-load environments

Multiple Compressors (Lead / Lag Network)

  • Best for larger, multi-line plants where uptime is most important
  • Allows redundancy (N+1) for maintenance without downtime
  • Lets the system stage compressors on/off for efficiency

Additional Considerations When Selecting a Compressed Air System

  1. Oil-free vs. Oil-injected based on Air Quality: If you’re in life sciences, pharmaceutical, semiconductor, aerospace electronics, food packaging, or any strict cleanliness environment then oil-free may be required to hit ISO contamination classes. If not, oil-injected is often the right fit as long as filtration is appropriate.
  1. Build Capacity for Growth and Reliability: Don’t design today for “bare minimum” when expansions are already on your roadmap. Be intentional about future production growth, new automation equipment, shift expansions or seasonality.
  2. Don’t Forget the “Rest of the System”: Supporting components can also influence final system size, such as dryer and filters that need sizing for dew point and purity, receivers that handle bursts and stabilize pressure, and piping/layout that reduce pressure loss and provide low friction paths.

If all the components of a compressed air system seem complicated, move your industrial air compressor to a single compressed air utility system.

DIRECTAIR® takes away the headache of managing a compressed air system and turns it into a fully managed utility service. For a fixed monthly rate, the DIRECTAIR® team engineers, installs, and maintains the properly sized compressed air system for you. No capital expense needed.

Contact DIRECTAIR® today to turn your air compressor challenges into a fully managed utility.

Step 3: Estimate Total Cost and Compare Options

The largest portion of your compressed air system’s cost isn’t the equipment purchase; it’s the energy to run it. In fact, for most manufacturing plants, energy use accounts for 70% or more of the lifecycle cost of a compressed air system.

Why Right-Sizing and Efficiency Matter

When a system is sized correctly and controls are optimized, the compressor operates closer to its best efficiency point instead of wasting energy at part-load.

DIRECTAIR® improves this even further by combining VSD operation, intelligent sequencing, advanced monitoring, and energy-efficient system design. That’s how DIRECTAIR® routinely delivers up to 50% energy savings, which lowers utility spend and reduces carbon emissions for facilities pursuing sustainability and ESG goals.

What to Evaluate When Comparing System Options

When comparing options, it’s essential to consider how efficiently a system performs at your average load, not just whether it can handle the maximum theoretical peak. Oversized compressors cycle more often, waste energy during idle/unload conditions, and run further away from their most efficient operating point. Well-sized storage capacity and smart controls are almost always a better way to handle short bursts of demand than installing excess horsepower that rarely gets used.

DIRECTAIR® utilizes an intelligent system automation called MANAGAIR® to cut energy waste, enhance reliability and deliver real-time monitoring to help you run leaner, smarter, and more reliably.

Reliability and Sustainability

Long-term reliability and uptime need to factor into cost modeling as well. Plants should consider how easily maintenance can be performed, whether redundancy exists to prevent unplanned downtime, and how pressure stability holds during high-demand events.

DIRECTAIR® addresses this operational layer by providing compressed air as a utility and guaranteeing performance, ensuring redundancy is built in from day one, and actively managing leak reduction and efficiency optimization. All of this reduces wasted kWh, lowers carbon output, and supports measurable sustainability improvement without requiring additional capital investment from the plant.

How DIRECTAIR® Helps

DIRECTAIR® is not just a compressor supplier. We provide compressed air as a utility. That means your facility requires no capital equipment purchase and no maintenance burden, all while giving you built-in capacity, redundancy and guaranteed performance.

See how DIRECTAIR® can turn your industrial compressed air burden into a managed utility service solution.

Book a Meeting to talk to DIRECTAIR® today!

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