What is the purpose of a glass gauge in a boiler?

The primary purpose of a glass gauge, also known as a sight glass, in a boiler is to indicate the water level within the boiler. This is crucial for safe operation because it allows the operator to visually confirm that the water level is within the appropriate range. Maintaining the correct water level is essential for boiler safety; if the water level is too low, it can lead to overheating and potentially cause a catastrophic failure. Conversely, if the water level is too high, it could result in water entering the steam lines, which could damage the system or disrupt operations. Therefore, the glass gauge provides an immediate and clear visual indication of water levels, making it an indispensable tool in boiler maintenance and operation.