TL;DR
A water hammer arrester is a sealed device containing a cushion of air or gas behind a piston or bladder, installed on water supply lines to absorb the shock wave created when a valve snaps shut and moving water stops instantly. Fast solenoid valves on washing machines, dishwashers, and icemakers are the usual offenders, producing the bang that rattles pipes against framing.
What it means
A water hammer arrester is a sealed device containing a cushion of air or gas behind a piston or bladder, installed on water supply lines to absorb the shock wave created when a valve snaps shut and moving water stops instantly. Fast solenoid valves on washing machines, dishwashers, and icemakers are the usual offenders, producing the bang that rattles pipes against framing. Listed under ASSE 1010 and sized AA through F by fixture load, modern units screw onto laundry valves or tee into the lines near the offending fixture, replacing the old air-chamber stub pipes that waterlog within months.
Where it sits in the glossary
Water hammer arrester is part of the Trade jargon group inside the ProFix Directory glossary. Browse every term in this category from the glossary index.
Why Ohio homeowners should know it
This is a term Ohio homeowners encounter when reading contractor quotes, hiring paperwork, or inspection reports. Understanding it well enough to ask one good follow-up question is usually all the protection a homeowner needs.
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ProFix tools that touch this term
See also
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