{"id":4721,"date":"2026-09-23T23:15:51","date_gmt":"2026-09-24T06:15:51","guid":{"rendered":"https:\/\/www.26yc.com\/air-filter-maintenance-replacement-pressure-drop\/"},"modified":"2026-09-23T23:17:15","modified_gmt":"2026-09-24T06:17:15","slug":"air-filter-maintenance-replacement-pressure-drop","status":"publish","type":"post","link":"https:\/\/www.26yc.com\/ja\/air-filter-maintenance-replacement-pressure-drop\/","title":{"rendered":"Air Filter Maintenance and Replacement: Pressure Drop, Service Life, When to Change"},"content":{"rendered":"<h2>Watch the Pressure Drop, Not the Date<\/h2>\n<p>As a filter loads, its <strong>pressure drop (\u0394P)<\/strong> rises and the fan works harder. The rule: replace when \u0394P reaches the manufacturer&#8217;s <em>final<\/em> limit-typically about <strong>2\u00d7 the initial \u0394P<\/strong>-or when energy cost outweighs the filter price.<\/p>\n<h2>Typical Service Intervals<\/h2>\n<table border=\"1\" cellpadding=\"6\" cellspacing=\"0\">\n<thead>\n<tr>\n<th>Stage<\/th>\n<th>Initial \u0394P<\/th>\n<th>Replace at<\/th>\n<th>Typical life<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Primary G3\/G4<\/td>\n<td>20-45 Pa<\/td>\n<td>~90-100 Pa<\/td>\n<td>3-6 months<\/td>\n<\/tr>\n<tr>\n<td>Medium F5-F9<\/td>\n<td>45-90 Pa<\/td>\n<td>~130-180 Pa<\/td>\n<td>6-12 months<\/td>\n<\/tr>\n<tr>\n<td>HEPA H13\/H14<\/td>\n<td>100-250 Pa<\/td>\n<td>Per test \/ 2-3 yr<\/td>\n<td>1-3 years<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h2>How to Monitor<\/h2>\n<ul>\n<li>Fit a <strong>differential pressure gauge or manometer<\/strong> across each bank.<\/li>\n<li>Log readings monthly; trend the slope to predict changeout.<\/li>\n<li>Bag collapse, visible discolouration or odour breakthrough are visual cues.<\/li>\n<\/ul>\n<h2>Safe Changeout<\/h2>\n<ul>\n<li>Shut the fan, lock out, and use PPE for contaminated media.<\/li>\n<li>Disposable media: bag-in\/bag-out; never wash-and-reuse synthetics.<\/li>\n<li>HEPA: after install, run a <strong>PAO\/DOP leak scan<\/strong> to confirm integrity.<\/li>\n<li>Log every changeout with date, location and part number.<\/li>\n<\/ul>","protected":false},"excerpt":{"rendered":"<p>Replace filters on pressure drop, not the calendar. Learn to read a differential manometer, set final \u0394P limits, and plan safe changeout for primary, medium and HEPA stages.<\/p>","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[109],"tags":[],"class_list":["post-4721","post","type-post","status-publish","format-standard","hentry","category-filter"],"_links":{"self":[{"href":"https:\/\/www.26yc.com\/ja\/wp-json\/wp\/v2\/posts\/4721","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.26yc.com\/ja\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.26yc.com\/ja\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.26yc.com\/ja\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.26yc.com\/ja\/wp-json\/wp\/v2\/comments?post=4721"}],"version-history":[{"count":1,"href":"https:\/\/www.26yc.com\/ja\/wp-json\/wp\/v2\/posts\/4721\/revisions"}],"predecessor-version":[{"id":4730,"href":"https:\/\/www.26yc.com\/ja\/wp-json\/wp\/v2\/posts\/4721\/revisions\/4730"}],"wp:attachment":[{"href":"https:\/\/www.26yc.com\/ja\/wp-json\/wp\/v2\/media?parent=4721"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.26yc.com\/ja\/wp-json\/wp\/v2\/categories?post=4721"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.26yc.com\/ja\/wp-json\/wp\/v2\/tags?post=4721"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}