{"id":6538,"date":"2025-09-22T07:00:25","date_gmt":"2025-09-22T05:00:25","guid":{"rendered":"https:\/\/uws-technologie.de\/distinction-between-oenorm-h-5195-1-and-vdi-2035-what-heating-engineers-really-need-to-know\/"},"modified":"2025-09-22T07:55:56","modified_gmt":"2025-09-22T05:55:56","slug":"distinction-between-oenorm-h-5195-1-and-vdi-2035-what-heating-engineers-really-need-to-know","status":"publish","type":"post","link":"https:\/\/uws-technologie.de\/en\/distinction-between-oenorm-h-5195-1-and-vdi-2035-what-heating-engineers-really-need-to-know\/","title":{"rendered":"Distinction between \u00d6NORM H 5195-1 and VDI 2035 \u2013 what heating engineers really need to know"},"content":{"rendered":"<p>Imagine you&#8217;re sitting at the customer&#8217;s kitchen table. The new building is almost finished, the heat pump is gleaming in the boiler room \u2013 and the manufacturer&#8217;s documents are lying on the table. Suddenly, the big question arises: \u201c<em>Do we now have to follow the VDI 2035 or the \u00d6NORM?<\/em>\u201d<br \/>\nAnd you think: \u201cSo, which is it?\u201d \u2013 this is where it gets interesting. Because not all standards are the same, and the differences are not just an academic detail. They determine in everyday practice whether a system operates according to standards, whether you receive complaints, or whether the manufacturer honors the warranty.<\/p>\n<h2>VDI and \u00d6NORM \u2013 two worlds, one goal<\/h2>\n<p>Both sets of standards have the same basic objective: <strong>to protect heating systems from damage caused by incorrect water.<\/strong> But the perspective is different:<\/p>\n<ul>\n<li><strong>VDI (Association of German Engineers)<\/strong><br \/>\nTechnically oriented, practical, and with clear specifications. The VDI guidelines are considered the authoritative state of the art in Germany. Manufacturers of heat generators, pumps, and fittings regularly refer to <a href=\"https:\/\/uws-technologie.de\/en\/heating-water-vdi-2035\/\">VDI 2035<\/a> when it comes to warranty or guarantee conditions.<\/li>\n<li><strong>\u00d6NORM (Austrian Standards Institute)<\/strong><br \/>\nFirmly anchored in law, more detailed in system consideration, and binding in Austria. While the VDI is a guideline, the \u00d6NORM is contractually required in many projects and is therefore more binding.<\/li>\n<\/ul>\n<p>In short: VDI shows you <strong>how to do it correctly from a technical perspective<\/strong>, while \u00d6NORM <strong>specifies even more precisely what you must comply with<\/strong>.<\/p>\n<h3>VDI 2035 \u2013 the classic in Germany<\/h3>\n<p>The <strong>VDI 2035 \u201cPrevention of Damage in Hot Water Heating Systems\u201d<\/strong> is the best-known guideline in the German HVAC trade. It clearly describes how heating water must be conditioned to prevent corrosion, scale, and other damage.<br \/>\nEspecially important:<\/p>\n<ul>\n<li>Limit values for <strong>total hardness<\/strong> and <strong>conductivity<\/strong>, graduated according to boiler output.<\/li>\n<li>Recommendations for the <strong>pH value<\/strong> (usually 8.2\u201310, for aluminum 8.2\u20139).<\/li>\n<li>Focus on the <strong>prevention of scaling and corrosion<\/strong>.<\/li>\n<\/ul>\n<p>VDI 2035 is therefore a very practical guideline \u2013 it helps you quickly decide in everyday situations: Treat the water or not?<\/p>\n<h3>\u00d6NORM H 5195-1 \u2013 the Austrian sister with its own signature<\/h3>\n<p>The <strong>\u00d6NORM H 5195-1 \u201cPrevention of Damage in Hot Water Heating Systems\u201d<\/strong> goes deeper than the VDI in many respects.<br \/>\nIt not only describes <strong>which water quality must be maintained<\/strong>, but also <strong>how to achieve it<\/strong> \u2013 and that makes it much more comprehensive:<\/p>\n<ul>\n<li>Exact specifications for the <strong>design of treatment systems<\/strong>.<\/li>\n<li><strong>Detailed limit values<\/strong> for conductivity, pH value, and hardness.<\/li>\n<li>Higher requirements for <strong>monitoring and follow-up<\/strong>: The system must not only be correct at start-up, it must be monitored continuously.<\/li>\n<\/ul>\n<p>In Austria, this means for you: The \u00d6NORM is not a \u201cmay\u201d, but a \u201cmust\u201d. Clients, planners, and authorities demand compliance \u2013 deviations can quickly become a problem.<\/p>\n<h3>The key differences between VDI 2035 and \u00d6NORM H 5195-1<\/h3>\n<p>So you can quickly keep track in everyday life, here are the core topics compared:<\/p>\n<ul>\n<li><strong>Binding nature<\/strong>\n<ul>\n<li><em>VDI 2035<\/em>: Guideline, state of the art in Germany, often required by manufacturers as a prerequisite.<\/li>\n<li><em>\u00d6NORM H 5195-1<\/em>: Standard, binding in Austria and often contractually stipulated.<\/li>\n<\/ul>\n<\/li>\n<li><strong>Level of detail<\/strong>\n<ul>\n<li><em>VDI 2035<\/em>: Focus on prevention of scaling and corrosion, practical limit values.<\/li>\n<li><em>\u00d6NORM H 5195-1<\/em>: Additional requirements for planning and design.<\/li>\n<\/ul>\n<\/li>\n<li><strong>Documentation &amp; monitoring<\/strong>\n<ul>\n<li><em>VDI 2035<\/em>: Measurements recommended at commissioning, annual maintenance, and operational disturbances.<\/li>\n<li><em>\u00d6NORM H 5195-1<\/em>: Documentation and regular inspections required.<\/li>\n<\/ul>\n<\/li>\n<li><strong>System consideration<\/strong>\n<ul>\n<li><em>VDI 2035<\/em>: Focus on water quality.<\/li>\n<li><em>\u00d6NORM H 5195-1<\/em>: Holistic approach, including technology, maintenance, and operation.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<h3>What does this mean for you in practice?<\/h3>\n<p>If you work in Germany, you can&#8217;t get around VDI 2035 \u2013 it is the benchmark by which manufacturers base their guarantees.<br \/>\nIn Austria, the following applies: \u00d6NORM H 5195-1 is binding. Here, it is not enough to treat the heating water just once \u2013 you also have to prove that it remains within the target range over time.<\/p>\n<p>And no matter which side of the border you are on: The best solution is always to work with a system that <strong>covers both worlds<\/strong>. This is exactly what products like <a href=\"https:\/\/uws-technologie.de\/en\/product\/vadion-ph-control\/\"><strong>Vadion pH-Control<\/strong><\/a> in combination with <strong>UWS devices<\/strong> are made for \u2013 they automatically provide you with the correct values and ensure that you meet both the VDI requirements and the \u00d6NORM specifications.<\/p>\n<div class=\"one-col-produktbox\"><div class=\"produktbox-center\"><div class=\"produktbox-images\"><div class=\"produktbox-symbol\" style=\"background-image:url(https:\/\/uws-technologie.de\/wp-content\/plugins\/fley-functions\/Mr_Heaty_Produkt.svg);\"><\/div><img decoding=\"async\" style=\"max-height:150px;\" src=\"https:\/\/uws-technologie.de\/wp-content\/uploads\/vadion_ph_control_produktabbildung-300x300.webp\" srcset=\"https:\/\/uws-technologie.de\/wp-content\/uploads\/vadion_ph_control_produktabbildung-300x300.webp 300w, https:\/\/uws-technologie.de\/wp-content\/uploads\/vadion_ph_control_produktabbildung-150x150.webp 150w, https:\/\/uws-technologie.de\/wp-content\/uploads\/vadion_ph_control_produktabbildung-250x250.webp 250w, https:\/\/uws-technologie.de\/wp-content\/uploads\/vadion_ph_control_produktabbildung-260x260.webp 260w, https:\/\/uws-technologie.de\/wp-content\/uploads\/vadion_ph_control_produktabbildung-270x270.webp 270w, https:\/\/uws-technologie.de\/wp-content\/uploads\/vadion_ph_control_produktabbildung-280x280.webp 280w, https:\/\/uws-technologie.de\/wp-content\/uploads\/vadion_ph_control_produktabbildung-290x290.webp 290w, https:\/\/uws-technologie.de\/wp-content\/uploads\/vadion_ph_control_produktabbildung-320x320.webp 320w, https:\/\/uws-technologie.de\/wp-content\/uploads\/vadion_ph_control_produktabbildung-335x335.webp 335w, https:\/\/uws-technologie.de\/wp-content\/uploads\/vadion_ph_control_produktabbildung-371x371.webp 371w, https:\/\/uws-technologie.de\/wp-content\/uploads\/vadion_ph_control_produktabbildung-374x374.webp 374w, https:\/\/uws-technologie.de\/wp-content\/uploads\/vadion_ph_control_produktabbildung-600x600.webp 600w, https:\/\/uws-technologie.de\/wp-content\/uploads\/vadion_ph_control_produktabbildung.webp 700w\" sizes=\"(max-width: 300px) 100vw, 300px\" class=\"produktbox-icon\" alt=\"Mixed bed resin Vadion pH-Control from UWS\" \/><\/div><h3>Mischbettharz Vadion pH Control<\/h3>Our Vadion pH-Control is a mixed bed resin that not only desalinates the water to &lt; 100 \u03bcS\/cm (equivalent to 0-2 \u00b0fh) but also ensures that the pH value of the filling water is within the required range.<br \/><a style=\"background-color: #00933b;\" class=\"btn button-green position-center\" href=\"https:\/\/uws-technologie.de\/product\/vadion-ph-control\/\" aria-label=\"Weiterf\u00fchrende Informationen zum Produkt: Mischbettharz Vadion pH Control\" rel=\"noopener\" role=\"button\">To the product<\/a><\/div><\/div>\n<h3>Conclusion<\/h3>\n<p>Whether VDI 2035 or \u00d6NORM H 5195-1 \u2013 both standards have the same goal: to prevent damage and protect systems in the long term. The difference lies in the <strong>binding nature<\/strong> and in the <strong>level of detail<\/strong>.<br \/>\nFor you as a heating engineer, this means: Understand the differences, know the requirements of your market \u2013 and work with solutions that give you the confidence to cover all requirements.<\/p>\n<p>\ud83d\udc49 With <strong>Vadion pH-Control<\/strong> and the matching UWS devices, you are on the safe side \u2013 in Germany as well as in Austria.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Imagine you&#8217;re sitting at the customer&#8217;s kitchen table. The new building is almost finished, the heat pump is gleaming in the boiler room \u2013 and the manufacturer&#8217;s documents are lying on the table. Suddenly, the big question arises: \u201cDo we now have to follow the VDI 2035 or the \u00d6NORM?\u201d And you think: \u201cSo, which [&hellip;]<\/p>\n","protected":false},"author":8,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"categories":[234,217,237,215,238],"tags":[],"class_list":["post-6538","post","type-post","status-publish","format-standard","hentry","category-filtration-en","category-make-up","category-mixed-bed-resin","category-preparation","category-shk-measurement-technology"],"acf":[],"_links":{"self":[{"href":"https:\/\/uws-technologie.de\/en\/wp-json\/wp\/v2\/posts\/6538","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/uws-technologie.de\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/uws-technologie.de\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/uws-technologie.de\/en\/wp-json\/wp\/v2\/users\/8"}],"replies":[{"embeddable":true,"href":"https:\/\/uws-technologie.de\/en\/wp-json\/wp\/v2\/comments?post=6538"}],"version-history":[{"count":1,"href":"https:\/\/uws-technologie.de\/en\/wp-json\/wp\/v2\/posts\/6538\/revisions"}],"predecessor-version":[{"id":6540,"href":"https:\/\/uws-technologie.de\/en\/wp-json\/wp\/v2\/posts\/6538\/revisions\/6540"}],"wp:attachment":[{"href":"https:\/\/uws-technologie.de\/en\/wp-json\/wp\/v2\/media?parent=6538"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/uws-technologie.de\/en\/wp-json\/wp\/v2\/categories?post=6538"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/uws-technologie.de\/en\/wp-json\/wp\/v2\/tags?post=6538"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}