What is the purpose of a water hammer arrestor installed near a quick-closing valve, such as a washing machine solenoid valve?
Not quite. The answer is D: To absorb the pressure surge from sudden valve closure, preventing pipe damage
A quick-closing valve stops a moving column of water almost instantly, and that momentum has to go somewhere — an arrestor's air chamber or piston absorbs the resulting pressure spike instead of letting it slam into the nearest fitting or joint.
Checked against the 2021 UPC text. Washington's exam is written against the 2015 edition, which we have not read for this section, so confirm it against your 2015 book.
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