How should air compressors be maintained in winter?

In cold winters, low temperatures can lead to equipment malfunctions if air compressors are not properly maintained. Many failures occur due to prolonged shutdowns without antifreeze protection, resulting in cracked coolers or startup issues. Below are key maintenance points to prevent winter-related compressor failures:

1. For machines that have been idle for extended periods or with long-used oil filters, replace the oil filter before startup. This prevents insufficient lubrication caused by thickened oil clogging the filter, which could trigger instant overheating and mechanical failure during startup.

2. After powering off, manually rotate the main unit coupling to check flexibility. Do not force startup if rotation is stiff—inspect for mechanical/motor issues or thickened/expired lubricant first.

3. Ensure oil temperature remains above +2°C before startup. Use heating devices to warm the oil-gas tank and main unit if temperatures are too low.

4. Verify oil levels are normal and all condensate drain ports are closed (open during long shutdowns). For water-cooled units, confirm cooling water drain valves are closed (keep open during extended downtime).

5. For two-stage compression systems (especially high-power models): – Add proper lubricant to the air intake before initial startup after prolonged shutdowns – Perform 2-3 jogging operations – Fully open the oil regulation valve from the oil-gas tank to the main unit during startup – Adjust cooling water flow to stabilize temperature if discharge air is too cold post-startup – Fine-tune oil intake via regulation valve based on actual operating temperatures.

6. For VFD compressors: – Monitor winter discharge temperatures to prevent excessive cooling (common during prolonged low-frequency operation) – Adjust cooling water valve openings according to discharge temperatures – Consider installing high-temperature thermal control valves if necessary to prevent oil emulsification.