Question 30General Subjects - QMED

70% to pass

When determining the level of a potable water hydro-pneumatic header tank fitted with a tubular sight glass, what must be taken into consideration?

AThe sight glass must be drained, blown down, and re-filled before each reading is taken.
BThe actual water level in the hydro-pneumatic header tank is somewhat higher than the level shown in the sight glass.
CThe actual water level in the hydro-pneumatic header tank is somewhat lower than the level shown in the sight glass.
DThe actual water level in the hydro-pneumatic header tank is identical to the level shown in the sight glass.
AI Explanation

The correct answer is D) The actual water level in the hydro-pneumatic header tank is identical to the level shown in the sight glass. This is because the water level in a hydro-pneumatic header tank with a tubular sight glass will accurately reflect the actual water level in the tank. The sight glass is designed to provide a direct visual indication of the water level, and there should be no discrepancy between the level shown and the true level in the tank. Options B and C are incorrect because the sight glass is not distorting the water level reading. Option A is incorrect because there is no need to drain, blow down, and re-fill the sight glass before each reading, as the level will be accurate without this extra step.

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