USCG Exam PracticeWatch duties, terminology, and instrumentation
What is the primary purpose of blowing down the gauge glass on a boiler watch?
- A. To reduce drum pressure before securing the fires
- ✓ To verify that the glass connections are clear and the indicated water level is accurateCorrect
- C. To activate the automatic feedwater regulator
- D. To test the low-water fuel cutout trip function
Why B is correct
NAVEDTRA 14104 §4-2 explains that blowing down the gauge glass — opening the drains to clear the connections — confirms the level returns promptly and reads truly, preventing a stuck or falsely high reading from masking a real low-water condition.
Cited:NAVEDTRA 14104 §4-2