{"id":6864,"date":"2026-05-08T12:16:33","date_gmt":"2026-05-08T12:16:33","guid":{"rendered":"https:\/\/www.airvision.be\/?p=6864"},"modified":"2026-05-08T12:23:24","modified_gmt":"2026-05-08T12:23:24","slug":"temperature-du-gaz-a-lallumage","status":"publish","type":"post","link":"https:\/\/www.airvision.be\/en\/temperature-du-gaz-a-lallumage\/","title":{"rendered":"Pitfalls #1 &#8211; Gas temperature at start-up"},"content":{"rendered":"\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"266\" src=\"https:\/\/www.airvision.be\/wp-content\/uploads\/image-1-1024x266.png\" alt=\"\" class=\"wp-image-6854\" srcset=\"https:\/\/www.airvision.be\/wp-content\/uploads\/image-1-1024x266.png 1024w, https:\/\/www.airvision.be\/wp-content\/uploads\/image-1-300x78.png 300w, https:\/\/www.airvision.be\/wp-content\/uploads\/image-1-768x199.png 768w, https:\/\/www.airvision.be\/wp-content\/uploads\/image-1-1536x399.png 1536w, https:\/\/www.airvision.be\/wp-content\/uploads\/image-1.png 2003w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\">Gas temperature at start-up: why it distorts fan selection<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>\u201cBut we provided the correct operating conditions\u2026\u201d<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This is a sentence we hear frequently after a difficult commissioning.<br>On paper, everything looked right: the fan was selected for the nominal operating conditions. Yet at start-up, the motor trips or the absorbed current exceeds the limits.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">In most cases, the root cause is the same: transient operating conditions, and especially gas temperature at start-up, were not considered.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>The classic pitfall: focusing only on steady-state operation<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Most fan inquiries include:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>airflow,<\/li>\n\n\n\n<li>pressure losses,<\/li>\n\n\n\n<li>nominal gas temperature.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">That makes sense \u2014 but it is often incomplete.<br>In many industrial processes, the fan does not start under nominal conditions.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">At start-up, the gas is usually:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>colder,<\/li>\n\n\n\n<li>and therefore denser.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">This difference has a direct impact on fan behavior.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Why a lower temperature matters<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">At constant speed, higher gas density results in:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>higher developed pressure,<\/li>\n\n\n\n<li>higher absorbed power,<\/li>\n\n\n\n<li>and therefore a real risk of motor overload.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">A fan that is perfectly suited for nominal operation may become electrically out of limits at start-up, simply because the actual gas temperature was overlooked.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">&#x1f449; The gas temperature at start-up, and more broadly transient operating conditions, are not a detail.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>The supplier\u2019s role\u2026 and the importance of context<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A good supplier will be able to guide you through this reasoning and challenge the data.<br>But this is only possible if the initial request provides enough context.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A selection based solely on nominal conditions limits the ability to:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>anticipate critical phases,<\/li>\n\n\n\n<li>secure start-up,<\/li>\n\n\n\n<li>recommend the right solutions (VSD, start-up strategy, motor margins).<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">The quality of the selection directly depends on the quality of the information shared.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Key takeaway<\/strong><br>Most start-up issues are not caused by a \u201cbad fan\u201d,<br>but by a selection based on an incomplete operating scenario.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">In this Pitfalls in Selecting Fans series, we will continue sharing these real-life lessons from the field.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Gas temperature at start-up: why it distorts fan selection \u201cBut we provided the correct operating conditions\u2026\u201d This is a sentence we hear frequently after a difficult commissioning.On paper, everything looked [&hellip;]<\/p>\n","protected":false},"author":3,"featured_media":6860,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-6864","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-technical-articles"],"_links":{"self":[{"href":"https:\/\/www.airvision.be\/en\/wp-json\/wp\/v2\/posts\/6864","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.airvision.be\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.airvision.be\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.airvision.be\/en\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/www.airvision.be\/en\/wp-json\/wp\/v2\/comments?post=6864"}],"version-history":[{"count":1,"href":"https:\/\/www.airvision.be\/en\/wp-json\/wp\/v2\/posts\/6864\/revisions"}],"predecessor-version":[{"id":6866,"href":"https:\/\/www.airvision.be\/en\/wp-json\/wp\/v2\/posts\/6864\/revisions\/6866"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.airvision.be\/en\/wp-json\/wp\/v2\/media\/6860"}],"wp:attachment":[{"href":"https:\/\/www.airvision.be\/en\/wp-json\/wp\/v2\/media?parent=6864"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.airvision.be\/en\/wp-json\/wp\/v2\/categories?post=6864"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.airvision.be\/en\/wp-json\/wp\/v2\/tags?post=6864"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}