15 Common Problems and Solutions for Mobile Air Compressors

Mobile air compressors are essential tools for various industries, offering flexibility and strong performance in locations without direct access to electrical power. However, like all machinery, they can encounter issues over time. Most failures in diesel-powered mobile air compressors are caused by small, often overlooked problems. If ignored, these minor issues can lead to serious damage and costly repairs.

In this guide, we’ll cover 15 common problems with mobile air compressors and provide practical solutions to help you keep your equipment running efficiently.

1.  Compressor Won’t Start

Cause:
No control voltage, damaged time relays, or a blown fuse.

Solution:
Check for control voltage. If present, inspect the time relays and electrical components. Replace faulty parts. If there’s no voltage, replace the fuse.

2. No Air Supply

Cause:
The control cylinder may not be working, the butterfly valve might be stuck, or the solenoid valve (ISV) coil isn’t activating.

Solution:
Inspect each component and repair or replace as needed.

3.  Low Exhaust Pressure

Cause:
Leaks in hoses or joints, or incorrect pressure settings.

Solution:
Check all connections for leaks and verify the pressure setting is appropriate.

4.  High Exhaust Temperature

Cause:
Possible reasons include:

• Low or poor-quality lubricating oil

• Clogged filters

• Cooling fan failure

• Malfunctioning temperature control valve

Solution:
Check the oil level and quality, clean or replace filters, and ensure the fan is working properly.

5.  Excessive Oil Consumption

Cause:
High oil content in condensate, too much lubricating oil, or blockages in the oil separator or return pipe.

Solution:
Inspect and clean the separator and pipes. Adjust the oil level to within the recommended range.

6. Automatic Shutdown

Cause:
High temperature, pressure issues, or a stopped cooling fan motor.

Solution:
Check the system display for alerts and resolve the underlying issue.

7.  High Working Pressure

Cause:
Overpressure (e.g., above 15 bar), incorrect load settings, or a faulty pressure regulator.

Solution:
Check the pressure settings, load sensors, and call for professional maintenance if needed.

8.  Motor Running in the Wrong Direction

Cause:
Incorrect wiring or failed switching in the star/delta controller.

Solution:
Check the motor’s wiring, including the live and neutral lines.

9.  Solenoid Valve Not Working

Cause:
Loose or damaged relays and connectors.

Solution:
Inspect all connections and replace faulty components.

10.  Cooling System Malfunction

Cause:
Non-rotating or damaged fan blades, worn-out relays, or loose wiring.

Solution:
Check the fan and motor, and repair or replace damaged parts.

11.  Worn-Out Belt

Cause:
The drive belt connecting the diesel engine and compressor is broken or slipping.

Solution:
Replace the belt and inspect the alignment.

12.  Low Oil Pressure

Cause:
Low oil levels, oil leakage, clogged filters, or valve spring issues.

Solution:
Top up the oil and inspect all related components for leaks or clogs.

13.  Electrical Faults

Cause:
Problems in the electrical protection or temperature control circuits.

Solution:
Have a technician inspect the circuits and repair damaged parts.

14.  Low Main Pipe Pressure

Cause:
Blocked air filter, leaking intake pipe, faulty solenoid valve, or pipeline leakage.

Solution:
Inspect and clean the air filter, check for leaks, and test the solenoid valve function.

15. Frequent Loading and Unloading

Cause:
Improper settings for load and unload pressure.

Solution:
Adjust the working pressure thresholds to reduce unnecessary cycling.

 Keep Your Mobile Air Compressor Running Smoothly

Routine checks and proper maintenance are key to preventing issues with mobile air compressors. Whether you’re using them on construction sites, in mining operations, or for industrial processes, addressing small problems early can save time and avoid costly downtime.

If you’re unsure about any repair or if the issue persists, always consult a qualified technician.

 Want to Learn More?

For more insights on mobile air compressor prices, selection guides, top brands, or custom solutions, feel free to contact Dequan Electromechanical. Our experts are ready to help you choose the right equipment and ensure it operates smoothly.

Sollant diesel portable air compressor