Compressed Air Audits

Discuss the potential benefits of compressed air audits in Charlotte NC, Raleigh NC, Greensboro NC, and Lynchburg VA with Lewis Systems Compressed Air Audit Professionals. Measuring flow (scfm), power (kW), and pressure (psi) presents an accurate profile used to determine Dynamic Efficiency. This data tells us what cost-saving options benefit you: Options that will improve your energy efficiency and save thousands of dollars in operating cost. Contact Lewis Systems today for an air audit.

compressed air audit

Top 10 Reasons for a Compressed Air Audit

  1. Find and Stop Leaks
  2. Reduce Unnecessary Pressure
  3. Set the Correct Air Pressure: Make Supply Meet Demand
  4. Replace “T” connections: Less turbulence = Less pressure loss
  5. Replace Old, Corroded or Wrong-Sized Pipes
  6. Remove Restrictions: Clogged Filters, Unused Equipment
  7. Evaluate Storage: Air Receiver + Compressed Air Piping
  8. Regulate Air Use: Air Costs more than Electricity
  9. Verify the Correct Pump for the job (Air vs Electric)
  10. Ensure Proper Maintenance


In the fall of 2008, Lewis Systems & Service was contracted by Graham-White to perform a supply side compressed air audit at our main manufacturing facility in Salem, VA. The audit was performed on two plant systems. The first system provides low pressure compressed air for general use in the manufacturing processes. The second system provides higher pressure air used in testing Graham-White’s products.

During the week-long audit Lewis Systems recorded flow, pressure and amps for each compressor at 12 second intervals. After the audit was complete, Graham-White was provided with a complete study showing all of the captured data along with recommendations for improvements.

In the case of the test air system, one of the recommendations was to simply designate a smaller, existing compressor as the primary unit and utilize another compressor to automatically trim the load based on demand. This small change promised to save Graham-White approximately $10k per year in energy costs.

The recommendation with the greatest money saving potential was to purchase and install a Gardner-Denver model VS80 variable speed rotary screw compressor. The variable speed machine adjusts its speed to the demand for air based on downstream system pressure. The projected energy savings was around $17k per year. After the machine was purchased and installed a justification audit was performed, the actual savings was over $21k.

Ben Grisso
Graham-White Manufacturing

Remote Monitoring

air compressor auditJoin the smart services revolution with cutting edge wireless technology.

What’s the best way to assure that your air compressors are being taken care of? The answer is, let Lewis Systems monitor them. Through Gardner Denver’s state of the art wireless technology, we can assure your compressors are properly maintained and serviced.

This will avoid unnecessary downtime by:
  • Resolving small problems before they become big ones
  • Immediate notification of advisories and alarms
  • 24/7 remote visibility of the compressor
  • Troubleshoot prior to site visit
  • Reduce response time
  • Manage maintenance scheduling
Wireless Advantages:
  • Eliminates time and expense of running CAT5
  • Eliminate IP configuration and network setup
  • Totally isolated from the IP network
  • No application software to load or maintain

Compressor Calculations and Formulas

CFM Calculator

Pipe Velocity Calculator

Receiver Selection & Sizing Analysis 

Learn About Lewis Systems Energy Audit Today!

  1. CFM of compressed air required to raise a known system pressure
    to a desired system pressure:C2 = Required CFM total
    C1 = Existing or known CFM
    P2 = Desired pressure
    P1 = Known PressureformulasEXAMPLE: A 75 HP Compressor rated at 320 CFM t 125 PSIG will hold only 85 PSI and we desire 125 PSI.C1 = 320 CFM
    P2 = 125 + 14.7 (139.7)
    P1 = 85 + 14.7 (99.7)
    C2 = 448.39 Total CFM requiredWe need an additional 128.39 CFM to raise system pressure to the desired level.
  2. Simple Energy Formula:Motor Efficiency = Cost per KW X .746 (Power Factor) X Hours of operation X Brake horse power*Note: No electric motor is 100% efficient, most will average 92-95% efficient.
  3. PSI VS. BHP (Rule of thumb):For every 1 PSIG pressure drop, BHP (Brake horsepower) goes down ½ %.