Overheating in rotary screw compressors is usually caused by restricted cooling, oil-related issues, or airflow problems. While the shutdown may look sudden, the root cause is often gradual and preventable.
Left unaddressed, high temperatures accelerate oil breakdown, increase bearing wear, and can cause air-end damage. Most overheating issues can be resolved with basic checks and proper maintenance—if caught early.
Rotary Screw Troubleshooting
Overheating – Rotary Screw Air Compressor Troubleshooting
High discharge temperatures causing shutdowns, often linked to cooling restrictions, oil issues, or ventilation problems.
Industrial systems
Field-tested diagnostics
Independent & unbiased
Safety Notice
Hot surfaces can cause burns. Allow the compressor to cool before inspecting the oil system or cooler. Lock out/tag out before removing guards or panels.
What this problem usually means
Check these first
5–10 minute checks before diving deeper
- Ambient temperature around the compressor (above 40°C/104°F is a problem)
- Ventilation and airflow—is hot exhaust air recirculating back to intake?
- Oil level on sight glass (should be between min/max marks)
- Oil condition—color, smell, any sign of contamination or breakdown
- Cooler cleanliness—dust, oil film, or debris blocking fins
- Cooling fan operation—is it spinning freely and in the correct direction?
- Air inlet filter condition—dirty filter restricts airflow
- Thermal valve operation (if accessible)—stuck closed prevents oil from reaching cooler
Common root causes
Why this happens in rotary screw compressors
Heat & cooling limitations
Insufficient airflow around the compressor, high ambient temperatures, or recirculation of hot exhaust air back into the intake.
Oil quality or flow issues
Degraded oil, wrong viscosity, low oil level, or restricted oil flow through the cooler or thermal valve.
Contaminated or clogged cooler
Dust, oil mist, or debris blocking cooler fins, reducing heat transfer capacity. Common in dusty environments.
Installation and ventilation problems
Compressor placed too close to walls, exhaust ducting undersized, or air intake pulling from a hot zone.
Maintenance gaps
Overdue oil changes, skipped filter replacements, or ignored temperature trends on the controller.
What NOT to do
Avoid replacing temperature sensors or thermostatic valves before confirming airflow, oil condition, and cooler cleanliness. Many overheating faults are misdiagnosed, leading to unnecessary part swaps and repeat failures.
Full Rotary Screw Troubleshooting Manual
Step-by-step diagnostics, root cause logic, and practical fixes for oil-injected rotary screw compressors. Save time and reduce downtime with proven methods.
- Step-by-step diagnostics for common failures
- Root cause analysis techniques
- Practical fixes with parts notes
- Works across all major brands