Overheating alarms and automatic shutdowns are the most frequent and impactful failures for air compressors. Long-term overheating or frequent shutdowns not only cut off air supply and halt production but also accelerate wear on core components, shorten service life, and may even cause oil ignition, cylinder seizure, or pipe bursting.
As summer approaches, the Jufeng team has summarized the most common overheating causes and solutions for customers.
Core Causes of Air Compressor Overheating
Overheating is caused by a combination of issues in the lubrication, cooling, operating conditions, environment, electrical controls, and components.
(1) Abnormal Lubrication System (Main Cause)
Air compressor oil provides lubrication, cooling, sealing, and noise reduction.
Insufficient oil: Low oil level due to consumption, leakage, or delayed refilling → poor heat dissipation → dry friction → rapid overheating.
Wrong oil type: Non-specified viscosity or low-quality oil → weak oil film → increased friction → poor cooling.
Oil degradation/contamination: Oil used overtime (normally 2000–4000 hours), oxidized, emulsified, or mixed with dust/metal chips → lost cooling and lubrication.
Oil circuit blockage: Clogged oil filter, faulty oil stop valve, or dirty oil pipes → insufficient oil supply → local overheating.
(2) Cooling System Failure (Most Common Cause)
The cooling system is the main heat-dissipation component.
Air-cooled units: Faulty fan motor, broken fan blades, loose belt, or dust-covered coolers → insufficient airflow → heat buildup.
Water-cooled units: Low cooling water level, failed water pump, high inlet temperature, or scaled pipes → poor heat exchange.
Cooler fouling: Internal blockage reduces heat exchange efficiency sharply.
(3) Abnormal Load & Operating Conditions
Long-term full load: Excessive air demand → continuous high-load operation → more heat than can be dissipated.
Over-pressure: Discharge pressure set too high → higher compression load → more heat and power consumption.
Minimum pressure valve failure: Stuck open → low internal pressure → insufficient oil circulation → overheating.
(4) Poor Operating Environment
High ambient temperature: Hot summer, enclosed workshop, or high-temperature area → high intake air temperature → difficult cooling.
Poor ventilation: Narrow space, blocked air ducts, or no exhaust fans → hot air recirculation.
High dust: Dust blocks coolers and air filters → lower cooling efficiency.
(5) Electrical & Control Component Faults
Temperature sensor fault: Aging or damaged sensor → false alarms or no alarm when overheating.
Thermostatic valve (thermal control valve) failure: Stuck or malfunctioning → cannot regulate oil temperature → high oil temperature.
Standard Overheating Troubleshooting Procedure
Follow the principle: Outside → Inside; Simple → Complex
Environment & Operating Conditions Check
Ambient temperature, ventilation, blocked ducts, discharge pressure, overload status.
Lubrication System Check
Oil level, oil quality, oil type, oil filter, oil circuit, oil stop valve.
Cooling System Full Check
Fan operation, belt tension, cooler cleaning;
Water level, water quality, water pump, pipe scaling (water-cooled).
Control Components Check
Temperature sensor, wiring, thermostatic valve operation.
Core Components Auxiliary Check
Air filter, oil separator, minimum pressure valve, intake condition.
Targeted Solutions
(1) Lubrication System Solutions
Fill to correct level with specified oil.
Replace degraded oil and oil filter.
Clean oil lines and repair/replace faulty oil stop valve.
(2) Cooling System Solutions
Air-cooled: Clean coolers; repair/replace fans, motors, or belts.
Water-cooled: Replenish water; improve water quality; descale pipes; repair pumps.
(3) Optimize Operating Conditions
Restore discharge pressure to rated value.
Avoid long-term overload.
Repair stuck minimum pressure valve.
(4) Improve Environment
Clear obstructions; improve ventilation.
Add sunshade or intake cooling in summer.
(5) Repair/Replace Controls
Replace faulty temperature sensors and calibrate.
Repair or replace stuck thermostatic valves.
Summary
Overheating faults involve lubrication, cooling, load, environment, and control systems.
Delayed handling will lead to serious damage, production stops, and safety risks.
If you cannot resolve the issue, please contact the Jufeng After-Sales Team for professional support.