Air filter, regulator, lubricator: do you need all three?

Air from a compressor is wet, dirty and often at a higher pressure than your machine needs. An FRL unit (filter, regulator, lubricator) cleans it up just before the machine. It saves valves and cylinders from wearing out early.

Filter

Catches water, rust and dirt from the pipes. A 5 micron element is the usual choice; 40 micron for rough jobs. Water collects in the bowl: choose an automatic drain if nobody will empty it every day.

Regulator

Holds the pressure steady, below the compressor’s pressure. Most machines run at about 6 bar. A steady pressure means the machine moves the same way every time.

Lubricator: often not needed

A lubricator adds a fine oil mist to the air. Most modern valves and cylinders are greased for life at the factory and do not need it. Older machines and air tools may. Be careful: once you start oiling, keep oiling, because the oil washes the factory grease away.

Size

Choose by the air flow, not only the thread. A unit that is too small looks fine at rest, but the pressure drops when the machine moves. If you do not know the flow, tell the seller how many cylinders move at once and their sizes.

Mount it close to the machine, with the bowl pointing down, and the arrow on the body in the direction of the air.