The impact of excessively high ambient temperatures on screw air compressor performance

GB 50029-2014 explicitly stipulates that the air compressor room shall be equipped with ventilation and cooling facilities to ensure that the indoor air temperature meets the operational requirements of the equipment;

During summer, the indoor temperature should not exceed 40°C. However, when the air compressor station is located in a confined space, in direct sunlight, or adjacent to heat sources (such as boilers, heat-treating equipment, and drying lines), the indoor temperature in summer often exceeds 45°C, and in some simple shed‑type stations even climbs above 50°C—far beyond the equipment’s design tolerance—leading to a concentrated occurrence of various failures and performance degradation.

The direct impact of excessively high ambient temperatures on the core performance of screw air compressors

1-High-temperature shutdown and alarm protection lead to interruptions in equipment operation continuity;

All screw air compressors are equipped with an intelligent temperature-control protection system, which serves as the final safeguard for the equipment.

When ambient temperatures exceed the allowable range and are compounded by the heat generated during compression, the head discharge temperature, oil‑gas tank temperature, and oil temperature can rise rapidly. Typically, screw compressors are set to shut down at a head‑overheat threshold of 105°C to 110°C; once this limit is reached, the control system immediately triggers a high‑temperature alarm and initiates shutdown protection. In poorly ventilated compressor rooms, units often trip on high‑temperature alarms repeatedly within just half an hour to an hour. Such frequent starts and stops not only disrupt the air supply but also subject the motor, contactors, and compressor head to mechanical stress. Some operators, in an attempt to keep production running, illegally raise the temperature‑control setpoints or bypass the protective circuits—practices that violate equipment safety‑operation standards, pose serious safety risks, and can easily lead to subsequent fires, compressor failures, and other severe accidents.

2-Lubricant degradation is accelerated, and its lubrication and cooling functions fail;

Lubricant viscosity drops rapidly, reducing oil-film strength; an effective protective film cannot form between the compressor rotor, bearings, and gears, leading to direct metal‑to‑metal friction and accelerated wear.

High temperatures accelerate oil oxidation and carbonization, causing rapid darkening of the lubricant, sludge formation, and carbon deposits that clog oil passages, oil filters, and temperature control valves.

Increased evaporation of the lubricant degrades oil–gas separation, raising the oil content in the compressed air while accelerating oil-level decline and shortening the oil‑change interval.

3-Fillter cartridges and seals have aged and failed, doubling the maintenance frequency.

At elevated temperatures, air filter paper becomes brittle and its pore structure deforms, reducing filtration accuracy and allowing dust to more easily enter the compressor’s interior, leading to rotor wear. Oil filters and oil–gas separators, exposed to hot lubricating oil, experience accelerated clogging of their internal media, increasing the pressure differential both inside and outside the equipment and further loading the system. Meanwhile, rubber and plastic components within the unit—such as seals, O-rings, hoses, and vibrationisolating pads—under prolonged hightemperature exposure harden, crack, and lose elasticity, directly causing oil and air leaks. Sealing failures at pipelines, valves, and flanged connections result in compressedair leakage; statistics show that leak rates in compressor stations under hightemperature conditions can be more than twice those observed at ambient temperatures.

4-The risk of motor and electrical component burnout has increased dramatically;

Electrical control cabinets are high‑failure‑rate areas. During summer’s extreme heat, the harsh operating environment inside—where precision electronic components such as variable frequency drives, PLCs, relays, and temperature sensors are housed—readily leads to signal malfunctions, component breakdowns, and short‑circuit tripping. Electrical faults are often sudden, resulting in unexpected equipment shutdowns; moreover, electrical components are expensive to repair and require lengthy downtimes, significantly disrupting continuous production.