1621317781 Automatic Drain Valve Condensate Drain Valve for Rotary Screw Air Compressor

Product Introduction

Discharges condensate without bleeding compressed air. 1621317781 is an automatic drain valve used on screw air compressor receivers, aftercoolers, and filter bowls to remove accumulated water and oil-water condensate. It opens on level or timed cycle and reseals before air loss, preventing rust, downstream moisture damage, and manual drain neglect. A sticking or clogged drain is a common hidden cause of water in the line, rising DP across filters, and corrosive buildup in tanks.

Key points buyers check

• Automatic operation — no manual petcock, no missed draining on night shifts or weekends.
• Anti-clog path — handles mixed condensate with fine rust and oil mist better than narrow orifices.
• Leak-safe closing — sealed seat stops continuous air blow-by that wastes compressor power.
• Verify before order — thread, port, voltage or float type, pressure range, and machine model; 1621317780/1621317781 are listed together but fitment must be checked by old label.
• Also called automatic drain valve, condensate drain valve, drainer valve, float drain valve.