{"id":414261,"date":"2026-01-22T10:00:00","date_gmt":"2026-01-22T09:00:00","guid":{"rendered":"https:\/\/poolcomet.com\/how-to-remove-air-from-the-pool-pump-how-to-bleed-it-and-when\/"},"modified":"2026-06-10T15:33:01","modified_gmt":"2026-06-10T14:33:01","slug":"how-to-remove-air-from-the-pool-pump-how-to-bleed-it-and-when","status":"publish","type":"post","link":"https:\/\/poolcomet.com\/en\/blog\/how-to-remove-air-from-the-pool-pump-how-to-bleed-it-and-when\/","title":{"rendered":"How to remove air from the pool pump, how to bleed it and when."},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">Knowing <strong>how to remove air from the pool pump<\/strong> is critical for the filtration system to work properly. Air in the circuit causes loss of flow, noise, overheating and overheating, and is one of the most frequent causes of breakdowns in domestic pumps.<\/p>\n\n<p class=\"wp-block-paragraph\">As professionals in maintenance and <a href=\"https:\/\/poolcomet.com\/filtracion-para-piscinas\/bombas-de-filtracion-para-piscina\/\" target=\"_blank\" rel=\"noreferrer noopener\">sale of pool pumps<\/a>, we explain how to remove air from the pump, how to bleed it properly, why air appears and when this problem indicates that the pump should be replaced with a new one.<\/p>\n\n<!--more-->\n\n<h2 class=\"wp-block-heading\">How to know if there is air in the pump<\/h2>\n\n<p class=\"wp-block-paragraph\">The clearest signs of air in the pool pump are:<\/p>\n\n<ul class=\"wp-block-list\">\n<li>Visible <strong>bubbles<\/strong> in the prefilter cover.<\/li>\n\n\n\n<li>The <strong>prefilter does not fill<\/strong> completely.<\/li>\n\n\n\n<li>Constant <strong>bubbly returns<\/strong>.<\/li>\n\n\n\n<li><strong>Irregular<\/strong> starting <strong>noise<\/strong>.<\/li>\n\n\n\n<li>The pump <strong>needs &#8220;help&#8221; to prime<\/strong>.<\/li>\n<\/ul>\n\n<p class=\"wp-block-paragraph\">If you identify any of these symptoms, you should purge the pump.<\/p>\n\n<h2 class=\"wp-block-heading\">How to purge the pool pump step by step<\/h2>\n\n<p class=\"wp-block-paragraph\">The professional procedure for removing air from the pool pump is as follows:<\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Turn off the pump<\/strong>. Never handle the prefilter cover while the pump is running.<\/p>\n\n<p class=\"wp-block-paragraph\"><strong>2. Open the prefilter cover<\/strong>. To do this, loosen the cap slowly to release pressure. Then, check that the o-ring is clean and in good condition.<\/p>\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"1024\" src=\"https:\/\/poolcomet.com\/wp-content\/uploads\/2023\/06\/tapa-prefiltro-bomba-kan-1024x1024.png\" alt=\"KAN Pump prefilter cover\" class=\"wp-image-258996\" style=\"width:600px\" title=\"\" srcset=\"https:\/\/poolcomet.com\/wp-content\/uploads\/2023\/06\/tapa-prefiltro-bomba-kan-1024x1024.png 1024w, https:\/\/poolcomet.com\/wp-content\/uploads\/2023\/06\/tapa-prefiltro-bomba-kan-300x300.png 300w, https:\/\/poolcomet.com\/wp-content\/uploads\/2023\/06\/tapa-prefiltro-bomba-kan-150x150.png 150w, https:\/\/poolcomet.com\/wp-content\/uploads\/2023\/06\/tapa-prefiltro-bomba-kan-768x768.png 768w, https:\/\/poolcomet.com\/wp-content\/uploads\/2023\/06\/tapa-prefiltro-bomba-kan-70x70.png 70w, https:\/\/poolcomet.com\/wp-content\/uploads\/2023\/06\/tapa-prefiltro-bomba-kan-1080x1080.png 1080w, https:\/\/poolcomet.com\/wp-content\/uploads\/2023\/06\/tapa-prefiltro-bomba-kan-1280x1280.png 1280w, https:\/\/poolcomet.com\/wp-content\/uploads\/2023\/06\/tapa-prefiltro-bomba-kan-980x980.png 980w, https:\/\/poolcomet.com\/wp-content\/uploads\/2023\/06\/tapa-prefiltro-bomba-kan-480x480.png 480w, https:\/\/poolcomet.com\/wp-content\/uploads\/2023\/06\/tapa-prefiltro-bomba-kan-600x600.png 600w, https:\/\/poolcomet.com\/wp-content\/uploads\/2023\/06\/tapa-prefiltro-bomba-kan-100x100.png 100w, https:\/\/poolcomet.com\/wp-content\/uploads\/2023\/06\/tapa-prefiltro-bomba-kan-460x460.png 460w, https:\/\/poolcomet.com\/wp-content\/uploads\/2023\/06\/tapa-prefiltro-bomba-kan.png 1500w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n<\/div>\n<p class=\"wp-block-paragraph\"><strong>3. Fill the prefilter with water<\/strong>. Use a hose or bucket to fill it completely. This step is key to recovering priming.<\/p>\n\n<p class=\"wp-block-paragraph\"><strong>4. Close the lid properly<\/strong>. Once closed, <a href=\"https:\/\/poolcomet.com\/en\/blog\/how-to-clean-pool-pump-filter-turbine-prefilter-and-sand\/\" target=\"_blank\" rel=\"noreferrer noopener\">clean<\/a> the o-ring seat. Then lubricate it with neutral petroleum jelly and, finally, tighten the cap again without forcing, ensuring tightness.<\/p>\n\n<p class=\"wp-block-paragraph\"><strong>5. Open suction valves<\/strong>. Make sure the skimmer and\/or bottom are fully open, avoiding partially closed valves.<\/p>\n\n<p class=\"wp-block-paragraph\"><strong>6. Start the pump<\/strong>. When you do, look at the prefilter. If the air comes out correctly, it will be completely filled in a few seconds.<\/p>\n\n<p class=\"wp-block-paragraph\"><strong>7. Additional purge (if sand filter is present)<\/strong>. Slightly open the filter bleeder until air-free water flows out. Then, close when the jet is continuous.<\/p>\n\n<h3 class=\"wp-block-heading\">How to remove air from the pool pump if it returns<\/h3>\n\n<p class=\"wp-block-paragraph\">If air reappears after purging, there is probably an air intake. To check, check:<\/p>\n\n<ul class=\"wp-block-list\">\n<li>Prefilter <strong>cover o-ring<\/strong>.<\/li>\n\n\n\n<li>Bottom drain <strong>plug<\/strong>.<\/li>\n\n\n\n<li><strong>Fittings and<\/strong> threaded <strong>joints<\/strong>.<\/li>\n\n\n\n<li>Suction <strong>valves<\/strong>.<\/li>\n\n\n\n<li><strong>Suction pipe<\/strong> with microcracks.<\/li>\n\n\n\n<li><strong>Water level<\/strong> (should be at the middle of the Skimmer).<\/li>\n<\/ul>\n\n<p class=\"wp-block-paragraph\">Our professional advice is to dry the outside of the pump and observe where bubbles or moisture appear at start-up.<\/p>\n\n<h3 class=\"wp-block-heading\">Common errors when bleeding or removing air from the pool pump.<\/h3>\n\n<ol class=\"wp-block-list\">\n<li>Do not fill the prefilter completely.<\/li>\n\n\n\n<li>Improper closing of the lid.<\/li>\n\n\n\n<li>Do not lubricate the o-ring.<\/li>\n\n\n\n<li>Start with closed valves.<\/li>\n\n\n\n<li>Purge only the filter and not the pump.<\/li>\n\n\n\n<li>Ignore suction leaks.<\/li>\n<\/ol>\n\n<p class=\"wp-block-paragraph\">These errors lead to recurrent debranching.<\/p>\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"800\" height=\"800\" src=\"https:\/\/poolcomet.com\/wp-content\/uploads\/2024\/04\/deteccion-de-fuga-de-agua-en-piscinas-9.jpg\" alt=\"Water leak detection in swimming pools\" class=\"wp-image-274527\" style=\"width:600px\" title=\"\" srcset=\"https:\/\/poolcomet.com\/wp-content\/uploads\/2024\/04\/deteccion-de-fuga-de-agua-en-piscinas-9.jpg 800w, https:\/\/poolcomet.com\/wp-content\/uploads\/2024\/04\/deteccion-de-fuga-de-agua-en-piscinas-9-300x300.jpg 300w, https:\/\/poolcomet.com\/wp-content\/uploads\/2024\/04\/deteccion-de-fuga-de-agua-en-piscinas-9-150x150.jpg 150w, https:\/\/poolcomet.com\/wp-content\/uploads\/2024\/04\/deteccion-de-fuga-de-agua-en-piscinas-9-768x768.jpg 768w, https:\/\/poolcomet.com\/wp-content\/uploads\/2024\/04\/deteccion-de-fuga-de-agua-en-piscinas-9-600x600.jpg 600w, https:\/\/poolcomet.com\/wp-content\/uploads\/2024\/04\/deteccion-de-fuga-de-agua-en-piscinas-9-100x100.jpg 100w, https:\/\/poolcomet.com\/wp-content\/uploads\/2024\/04\/deteccion-de-fuga-de-agua-en-piscinas-9-80x80.jpg 80w\" sizes=\"auto, (max-width: 800px) 100vw, 800px\" \/><\/figure>\n<\/div>\n<h2 class=\"wp-block-heading\">When Purging the Pool Pump Is Not Enough<\/h2>\n\n<p class=\"wp-block-paragraph\">Purging solves the problem if it is punctual. But it is not enough when the pump is daily de-primed, there are constant bubbles, the prefilter cover does not seal, the body is deformed, the motor seal is damaged or the pump is old and loses performance.<\/p>\n\n<p class=\"wp-block-paragraph\">In these cases, air is a symptom, not the main cause. You may choose to repair it if the pump is relatively new, the problem is the o-ring or a joint, or, if after purging, the system stabilizes.<\/p>\n\n<p class=\"wp-block-paragraph\">If your pump is 8 years old or older, continuously breaks down, has internal leaks or wear, overheats or stalls and produces high consumption, it is time to replace it to avoid repeated breakdowns and improve performance.<\/p>\n\n<p class=\"wp-block-paragraph\">The pump models we recommend in this case are from the <a href=\"https:\/\/poolcomet.com\/en\/blog\/espa-silen-nox-and-noxsalt-pump-catalog-12-to-1000m-and-0-33-to-3-hp\/\" target=\"_blank\" rel=\"noreferrer noopener\">ESPA pump range<\/a>. Depending on your needs, suitable models are <a href=\"https:\/\/poolcomet.com\/en\/swimming-pool-filtration-pumps\/espasilen-i-swimming-pool-pump\/\" target=\"_blank\" rel=\"noreferrer noopener\">Silen I<\/a> and <a href=\"https:\/\/poolcomet.com\/en\/swimming-pool-filtration-pumps\/espa-nox-jardino-swimming-pool-filtration-pump\/\" target=\"_blank\" rel=\"noreferrer noopener\">Nox<\/a> for small pools, <a href=\"https:\/\/poolcomet.com\/en\/swimming-pool-filtration-pumps\/espasilen-s-swimming-pool-pump\/\" target=\"_blank\" rel=\"noreferrer noopener\">Silen S<\/a> or <a href=\"https:\/\/poolcomet.com\/en\/swimming-pool-filtration-pumps\/espasilen-s2-swimming-pool-pump\/\" target=\"_blank\" rel=\"noreferrer noopener\">Silen S2<\/a> for medium or large pools and <a href=\"https:\/\/poolcomet.com\/en\/swimming-pool-filtration-pumps\/espa-noxsalt-marine-water-swimming-pool-filtration-pump\/\" target=\"_blank\" rel=\"noreferrer noopener\">NoxSalt<\/a> for salt chlorination or high salinity.<\/p>\n\n<h2 class=\"wp-block-heading\">Frequently asked questions about how to drain the pool pump<\/h2>\n\n<h3 class=\"wp-block-heading\">How to remove air from the pool pump quickly?<\/h3>\n\n<p class=\"wp-block-paragraph\">Turn off the pump, open the prefilter, fill it completely with water, check the o-ring, close it tightly and start with open valves. Purge the filter if necessary.<\/p>\n\n<h3 class=\"wp-block-heading\">Why does air come back in after purging?<\/h3>\n\n<p class=\"wp-block-paragraph\"><strong>Because there is air intake in aspiration<\/strong>. It may be due to a defective o-ring, improperly closed cap, loose fitting or low water level.<\/p>\n\n<h3 class=\"wp-block-heading\">Is it normal to have small bubbles on start-up?<\/h3>\n\n<p class=\"wp-block-paragraph\"><strong>Yes, for a few seconds<\/strong>. If they continue, it indicates persistent air and should be checked for leaks.<\/p>\n\n<h3 class=\"wp-block-heading\">Can I purge the pump when the pool is empty?<\/h3>\n\n<p class=\"wp-block-paragraph\"><strong>No<\/strong>. The pump should never run without water; you could damage it.<\/p>\n\n<h3 class=\"wp-block-heading\">What happens if the pump runs on air?<\/h3>\n\n<p class=\"wp-block-paragraph\">It loses performance, heats up, breaks down and can damage the mechanical seal and the motor.<\/p>\n\n<h3 class=\"wp-block-heading\">Does an old pump de-boil more?<\/h3>\n\n<p class=\"wp-block-paragraph\"><strong>Yes<\/strong>. Over the years, the o-rings and the body lose their tightness and the priming becomes unstable.<\/p>\n","protected":false},"excerpt":{"rendered":"Avoid failures and noises in your pool. Learn how to properly purge the pump and remove air that compromises its performance. Our professional maintenance guide explains symptoms, the step-by-step process, common mistakes and when persistent air indicates the need for an overhaul or replacement of your pump.","protected":false},"author":141,"featured_media":409268,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[3049],"tags":[],"class_list":["post-414261","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-pool-equipment"],"acf":[],"permalink_manager":null,"_links":{"self":[{"href":"https:\/\/poolcomet.com\/en\/wp-json\/wp\/v2\/posts\/414261","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/poolcomet.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/poolcomet.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/poolcomet.com\/en\/wp-json\/wp\/v2\/users\/141"}],"replies":[{"embeddable":true,"href":"https:\/\/poolcomet.com\/en\/wp-json\/wp\/v2\/comments?post=414261"}],"version-history":[{"count":0,"href":"https:\/\/poolcomet.com\/en\/wp-json\/wp\/v2\/posts\/414261\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/poolcomet.com\/en\/wp-json\/wp\/v2\/media\/409268"}],"wp:attachment":[{"href":"https:\/\/poolcomet.com\/en\/wp-json\/wp\/v2\/media?parent=414261"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/poolcomet.com\/en\/wp-json\/wp\/v2\/categories?post=414261"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/poolcomet.com\/en\/wp-json\/wp\/v2\/tags?post=414261"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}