{"id":1524,"date":"2026-05-18T17:56:30","date_gmt":"2026-05-18T22:56:30","guid":{"rendered":"https:\/\/plumbing101.i234.me\/wordpress\/?p=1524"},"modified":"2026-05-16T04:35:24","modified_gmt":"2026-05-16T09:35:24","slug":"washing-machine-water-hammer-fix-that-lasts","status":"publish","type":"post","link":"https:\/\/plumbing101.i234.me\/wordpress\/washing-machine-water-hammer-fix-that-lasts\/","title":{"rendered":"Washing Machine Water Hammer Fix That Lasts"},"content":{"rendered":"

Washing machines can be rough on plumbing. Their fast shutoff valves stop water very quickly.
\nThat sudden stop can cause water hammer. You may hear a bang, thump, or pipe shake.<\/p>\n

A homeowner asked a common question. Cheap water hammer arrestors behind the washer lasted
\nabout three years. Instead of buying new ones, they wanted to install old-style copper tube
\narrestors.<\/p>\n

Their plan was simple. Add tall copper tubes near the washer valves. Add a quarter-turn valve
\nand drain at the bottom. When the tubes fill with water, close the valves. Then drain the tubes.
\nAfter that, the air pocket would be restored.<\/p>\n

Question<\/h2>\n

Is there any reason not to make those copper tubes three to four feet tall?<\/p>\n

Answer<\/h2>\n

Yes. The main reason is that old-style air chambers can become waterlogged again.
\nTall copper tubes may also fail code in some areas. A listed water hammer arrestor is usually
\nthe better choice.<\/strong><\/p>\n

Old copper air chambers work by trapping air. That air cushions the moving water. Over time,
\nthe air can dissolve into the water. Then the chamber fills with water. Once that happens,
\nit stops helping.<\/p>\n

Making the tube taller may delay the problem. But it does not solve the main issue. The air
\npocket can still disappear. A three-foot or four-foot tube may also be hard to hide. It can
\nadd stress if it is not braced well.<\/p>\n

Many modern plumbing systems use mechanical arrestors instead. These devices use a sealed
\nchamber, piston, or similar part. They are made to absorb shock from fast-closing valves.
\nWashing machines are a common place to use them.<\/p>\n

Look for arrestors marked for the right standard and size. Oatey lists water hammer arrestors
\nfor single fixtures and multi-fixture use. You can read more from\u00a0Oatey<\/a>.
\nSome product sheets also mention ASSE 1010 and PDI WH-201 standards.<\/p>\n

Plumbing code can vary by state and city. The International Code Council explains plumbing
\ncode rules and model code updates. You can review their resources at the\u00a0International Code Council<\/a>.
\nFor local work, check with your building office.<\/p>\n

What I Would Do<\/h2>\n

I would not build four-foot homemade arrestors behind a washer. I would install quality,
\nlisted water hammer arrestors at the washer valves. I would also check the water pressure.
\nHigh pressure can make water hammer worse.<\/p>\n

If the first arrestors failed fast, buy a better grade this time. Also, make sure they are
\ninstalled close to the washer shutoff valves. Support loose pipes, too. Loose pipes can make
\nnormal water movement sound much worse.<\/p>\n

The old copper tube idea is clever. But it is not the best long-term fix. A listed arrestor
\nIt is cleaner, safer, smaller, and easier to service.<\/p>\n

I’m Chris Mayer, writing for Plumbing 101<\/a>.<\/p>\n

\"Washing
Washing Machine Water Hammer Fix That Lasts<\/figcaption><\/figure>\n","protected":false},"excerpt":{"rendered":"

Washing machines can be rough on plumbing. Their fast shutoff valves stop water very quickly. That sudden stop can cause water hammer. You may hear a bang, thump, or pipe shake. A homeowner asked a common question. Cheap water hammer arrestors behind the washer lasted about three years. Instead of buying new ones, they wanted… Continue reading Washing Machine Water Hammer Fix That Lasts<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":1526,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":"","_wpscp_schedule_draft_date":"","_wpscp_schedule_republish_date":"","_wpscppro_advance_schedule":false,"_wpscppro_advance_schedule_date":"","_wpscppro_dont_share_socialmedia":null,"_wpscppro_custom_social_share_image":0,"_facebook_share_type":"default","_twitter_share_type":"default","_linkedin_share_type":"default","_pinterest_share_type":"default","_linkedin_share_type_page":"","_instagram_share_type":"default","_medium_share_type":"default","_threads_share_type":"default","_google_business_share_type":"default","_selected_social_profile":[],"_wpsp_enable_custom_social_template":false,"_wpsp_social_scheduling":{"enabled":false,"datetime":null,"platforms":[],"status":"template_only","dateOption":"today","timeOption":"now","customDays":"","customHours":"","customDate":"","customTime":"","schedulingType":"absolute"},"_wpsp_active_default_template":true},"categories":[79],"tags":[1155,1154,257,109,1258,111,1257,1157,1255,115,343,512,1256,1153,233,1152,1156],"class_list":["post-1524","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-general-plumbing-help","tag-banging-pipes","tag-copper-air-chamber","tag-fix","tag-general","tag-hammer","tag-help","tag-lasts","tag-laundry-plumbing","tag-machine","tag-plumbing","tag-plumbing-repair","tag-that","tag-washing","tag-washing-machine-plumbing","tag-water","tag-water-hammer-arrestor","tag-water-hammer-fix","entry"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/plumbing101.i234.me\/wordpress\/wp-json\/wp\/v2\/posts\/1524","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/plumbing101.i234.me\/wordpress\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/plumbing101.i234.me\/wordpress\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/plumbing101.i234.me\/wordpress\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/plumbing101.i234.me\/wordpress\/wp-json\/wp\/v2\/comments?post=1524"}],"version-history":[{"count":1,"href":"https:\/\/plumbing101.i234.me\/wordpress\/wp-json\/wp\/v2\/posts\/1524\/revisions"}],"predecessor-version":[{"id":1527,"href":"https:\/\/plumbing101.i234.me\/wordpress\/wp-json\/wp\/v2\/posts\/1524\/revisions\/1527"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/plumbing101.i234.me\/wordpress\/wp-json\/wp\/v2\/media\/1526"}],"wp:attachment":[{"href":"https:\/\/plumbing101.i234.me\/wordpress\/wp-json\/wp\/v2\/media?parent=1524"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/plumbing101.i234.me\/wordpress\/wp-json\/wp\/v2\/categories?post=1524"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/plumbing101.i234.me\/wordpress\/wp-json\/wp\/v2\/tags?post=1524"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}