How to Read an Air Compressor Sight Glass

Reading an air compressor sight glass involves locating it and checking the oil level against a specific marker, typically a dot.

An air compressor sight glass is a small window, usually made of clear plastic or glass, that allows you to visually inspect the oil level inside the compressor pump or sump tank without opening it. Maintaining the correct oil level is crucial for the longevity and proper functioning of your air compressor.

Locating the Sight Glass

The location of the sight glass varies depending on the type of air compressor:

• Reciprocating Compressors: It may be found on the base of the pump.
• Rotary Screw Compressors: It is typically located on the sump tank.

The Key Indicator: The Dot

Once you've found the sight glass, look closely. In the middle of the sight glass, you will see a dot. This dot serves as the primary reference point for determining the correct oil level.

Reading the Oil Level

To read the oil level, observe where the oil line sits in relation to the dot:

• Ideal Level: Ideally, you want the oil level to be in the center of the dot. This indicates the oil is at the recommended level for operation.
• Low Level: If the oil level is below the dot, your unit needs more oil. Operating with insufficient oil can cause significant damage to the compressor components.

Here's a quick summary based on the reference:

Regularly checking your air compressor's sight glass and ensuring the oil level is at the recommended position (ideally in the center of the dot) is a simple yet vital part of routine maintenance that helps keep your equipment running smoothly.