When performing a periodic gauge glass blow...

🔍 Key Concepts

• Gauge glass blow down purpose – to prove the gauge passages to the boiler are clear and the glass is accurately showing water level • Difference between the top steam connection and the bottom water connection on a boiler gauge glass • Normal sequence of isolating and draining a gauge glass to test both top and bottom connections

💭 Think About

• Ask yourself: When you first start a blow down, do you want to verify the steam (top) side or the water (bottom) side of the gauge glass first, and why? • Think through what happens inside the glass and connections when you close the top valve versus when you close the bottom valve, then open the drain. • Which initial step makes it safest and easiest to confirm that water is freely entering and leaving the gauge glass from the boiler?

✅ Before You Answer

• Identify which valve (top or bottom) controls the water side connection to the boiler and which controls the steam side. • Make sure you understand that the drain valve must provide a clear flow path to prove that connection is open, not blocked. • Verify which end (top or bottom) you are actually clearing when only one shutoff valve is closed and the drain valve is opened.

When performing a periodic gauge glass blow down to insure that the glass is free and operating correctly, what action is performed first?

Close the bottom shut off valve and open the drain valve to clear out the bottom connection to the gauge glass.

Close the top shut off valve and open the drain valve to clear out the bottom connection to the gauge glass.

Close the bottom shut off valve and open the drain valve to clear out the top connection to the gauge glass.

Close the top shut off valve and open the drain valve to clear out the top connection to the gauge glass.

🔍 Key Concepts

💭 Think About

✅ Before You Answer