What is the purpose of blowing down the sight glass at the start of each shift?

The purpose of blowing down the sight glass at the start of each shift is to ensure accurate water level reading. The sight glass provides a visual indication of the water level in a boiler or other pressurized system. Over time, minerals, sediment, and other impurities can accumulate within the sight glass, leading to obscured visibility. By blowing down the sight glass, any buildup is removed, allowing for a clear view of the water level. This is crucial for safe operation, as an inaccurate reading could lead to issues such as low water conditions that might jeopardize the boiler's integrity or safety. Ensuring that the sight glass remains clean and clear is a vital step that contributes to effective monitoring and operational safety.