Troubleshooting & Common Issues in Screw Air Compressors

“A minor issue in your air system can turn into a major loss if ignored.”

Even the best screw air compressors and air dryers can face performance issues over time. Pressure drops, oil leaks, or vibration problems can affect productivity, increase energy costs, and reduce the compressor’s lifespan.

Here’s how to identify, troubleshoot, and fix the most common problems in compressed air systems.

 1. Diagnosing Pressure Drops in Rotary Screw Compressors

Pressure drop means your system is losing efficiency between the compressor and the point of use. If your air tools or machines aren’t getting enough pressure, start by checking these:

 Common Causes:

  • Clogged filters or dryers

  • Long or undersized air pipelines

  • Excess bends, fittings, or leaks

  • Blocked drain valves or separators

  • Malfunctioning pressure regulator

 Quick Fixes:

  • Clean or replace air filters regularly.

  • Use aluminum or SS pipelines instead of GI pipes to reduce pressure loss.

  • Maintain optimal system pressure between 6–8 bar depending on your process.

  • Keep your dryers and moisture separators serviced and drain-free.

“Every 1 bar of pressure loss increases your power cost by nearly 7%. Don’t let leaks drain your profit.”

 2. Identifying Leaks in Oil-Injected Systems

In oil-lubricated screw compressors, oil plays a key role in cooling, sealing, and lubrication. But oil leaks are among the most common (and costly) maintenance problems.

 Common Leak Points:

  • Loose hose connections or fittings

  • Cracked oil seals or O-rings

  • Faulty oil separators or drain valves

  • Overfilled oil tank or incorrect grade oil

 How to Detect Leaks:

  • Visually inspect around the oil separator tank and hoses.

  • Use soap-water spray on joints to spot bubbles.

  • Install an oil mist detector or inline monitor for preventive alerts.

Prevention Tips:

  • Follow manufacturer’s service intervals.

  • Replace oil filters and separators as per Comptech’s maintenance chart.

  • Always use recommended compressor oil (avoid automotive oils).

 3. Troubleshooting VFD Errors & Abnormal Vibrations

Modern screw compressors use Variable Frequency Drives (VFDs) for energy efficiency — but VFD issues can stop production if not handled properly.

 Common VFD Problems:

  • Voltage fluctuations or phase imbalance

  • Overcurrent or motor overload errors

  • Incorrect grounding or loose connections

  • Faulty pressure sensor input signals

 Troubleshooting Steps:

  • Check for loose wiring in VFD and motor terminals.

  • Ensure stable input voltage (±10% range).

  • Reset fault codes and monitor current draw on all three phases.

  • Verify motor bearings and coupling alignment to stop vibration.

 “A vibrating compressor is a warning sign — check coupling alignment and base bolts before it damages bearings.”

General Maintenance Checks

  • Check and clean air filters weekly.

  • Drain condensate automatically to avoid water buildup.

  • Ensure vibration pads are tight and intact.

  • Inspect dryer and drain connections monthly.

  • Record amp draw and air pressure daily to detect unusual load.

Prevention is Better Than Downtime

Routine monitoring can prevent most compressor failures.
At Comptech Compressors, our service experts provide:

  • Pressure and air quality audits

  • Oil separator and dryer maintenance

  • VFD fault diagnosis and correction

Call Comptech today for an on-site compressor health check-up and keep your system running at peak performance.
Visit: https://screwcompressorindia.com