{"id":7869,"date":"2020-09-29T16:07:00","date_gmt":"2020-09-29T14:07:00","guid":{"rendered":"https:\/\/www.idro-elettrica.it\/esperto-risponde\/fire-pumps-uni-en-12845-permitted-types\/"},"modified":"2026-07-01T09:46:30","modified_gmt":"2026-07-01T07:46:30","slug":"fire-pumps-uni-en-12845-permitted-types","status":"publish","type":"esperto-risponde","link":"https:\/\/www.idro-elettrica.it\/en\/esperto-risponde\/fire-pumps-uni-en-12845-permitted-types\/","title":{"rendered":"Fire Pumps UNI EN 12845: Permitted Types"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\"><em>UNI EN 12845 Fire Pumps<\/em>: If you want to clarify \u201conce and for all\u201d which pump types can be used for fire protection water supply systems, the answer starts with the relevant standards and the preferred hydraulic layout.<\/p>\n\n<div class=\"wp-block-rank-math-toc-block\" id=\"rank-math-toc\"><h2>Table of Contents<\/h2><nav><ul><li class=\"\"><a href=\"#riferimenti-uni-en-12845-2020-e-t-r-11438-2016\">References: UNI EN 12845:2020 and T\/R 11438:2016<\/a><\/li><li class=\"\"><a href=\"#tipologie-ammesse-elenco-sintetico\">Acceptable Types: Summary List<\/a><\/li><li class=\"\"><a href=\"#pompe-antincendio-uni-en-12845-e-schema-idraulico-perche-si-privilegia-il-sottobattente\">UNI EN 12845 Fire Pumps and Hydraulic Diagram: Why the Downpipe Configuration Is Preferred<\/a><\/li><li class=\"\"><a href=\"#vtp-vantaggio-dello-schema-e-impatto-sugli-ingombri\">VTP: Advantages of the Design and Impact on Overall Dimensions<\/a><\/li><li class=\"\"><a href=\"#quando-la-norma-ammette-il-soprabattente-e-perche-e-una-scelta-di-ripiego\">When the rules allow for a secondary floor (and why it is a \u201cfallback\u201d option)<\/a><\/li><li class=\"\"><a href=\"#alimentazioni-idriche-singola-e-singola-superiore-e-accoppiamento-dei-motori\">Water supplies: single and upper single, and engine coupling<\/a><\/li><li class=\"\"><a href=\"#pompe-sommerse-quando-usarle-e-come-giustificarle\">Submersible Pumps: When to Use Them and How to Justify Their Use<\/a><\/li><li class=\"\"><a href=\"#pompe-multistadio-e-axial-split-case-casi-duso-indicati\">Multistage and Axial Split-Case Pumps: Recommended Applications<\/a><\/li><li class=\"\"><a href=\"#conclusione\">Conclusion<\/a><\/li><\/ul><\/nav><\/div>\n\n<h2 id=\"riferimenti-uni-en-12845-2020-e-t-r-11438-2016\" class=\"wp-block-heading\">References: UNI EN 12845:2020 and T\/R 11438:2016<\/h2>\n\n<p class=\"wp-block-paragraph\">When discussing pumps that can be used to supply fire protection systems, the applicable standard is <strong>UNI EN 12845:2020<\/strong>, specifically <strong>Section 10.6.1<\/strong> and<strong>Appendix E<\/strong>.<\/p>\n\n<p class=\"wp-block-paragraph\">In addition to this standard, reference is also made to <strong>T\/R 11438:2016<\/strong>, <strong>section 8.4<\/strong>. In practice, to answer the question correctly, the Pump Types that are \u201cacceptable\u201d must be determined by considering these points together. <\/p>\n\n<h2 id=\"tipologie-ammesse-elenco-sintetico\" class=\"wp-block-heading\">Acceptable Types: Summary List<\/h2>\n\n<p class=\"wp-block-paragraph\">Following the order of the references cited, the applicable types are listed as follows:<\/p>\n\n<ul class=\"wp-block-list\">\n<li><strong>Section 10.6.1 of UNI EN 12845<\/strong>\n<ul class=\"wp-block-list\">\n<li><strong>Horizontal-axis centrifugal pumps<\/strong><\/li>\n\n\n\n<li><strong>Vertical Submersible Axial Flow Pumps (VTP)<\/strong><\/li>\n\n\n\n<li><strong>Submersible Pumps<\/strong><\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Appendix E to UNI EN 12845<\/strong>\n<ul class=\"wp-block-list\">\n<li><strong>Horizontal multistage pumps<\/strong><\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Item 8.4 T\/R 11438<\/strong>\n<ul class=\"wp-block-list\">\n<li><strong>Split-case pumps (axial split case)<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n<p class=\"wp-block-paragraph\">This list serves as a guide for making your selection: not all pumps are \u201cinterchangeable,\u201d and, above all, <strong>the installation configuration<\/strong> and <strong>specific requirements<\/strong> also matter.<\/p>\n\n<h2 id=\"pompe-antincendio-uni-en-12845-e-schema-idraulico-perche-si-privilegia-il-sottobattente\" class=\"wp-block-heading\">UNI EN 12845 Fire Pumps and Hydraulic Diagram: Why the Downpipe Configuration Is Preferred<\/h2>\n\n<p class=\"wp-block-paragraph\">For the hydraulic system, the <strong>SUBMERSIBLE<\/strong> configuration is \u201cobviously preferred.\u201d In practical terms, this means that, within the proposed decision-making process, the first pumps to be considered are <strong>horizontal-shaft centrifugal pumps<\/strong> installed in <strong>a submerged configuration<\/strong>. <\/p>\n\n<p class=\"wp-block-paragraph\">UNI EN 12845 also classifies <strong>vertical submersible axial-flow pumps (VTP)<\/strong> as having the same level of reliability, and these are <strong>also<\/strong> considered to be <strong>BELOW THE THRESHOLD<\/strong>. The key point is that, when you can remain below the threshold, that configuration is considered the reference standard. <\/p>\n\n<h2 id=\"vtp-vantaggio-dello-schema-e-impatto-sugli-ingombri\" class=\"wp-block-heading\">VTP: Advantages of the Design and Impact on Dimensions<\/h2>\n\n<p class=\"wp-block-paragraph\">A \u201cmajor advantage\u201d of the <strong>VTP<\/strong> system over the <strong>centrifugal pump<\/strong> system is highlighted: the <strong>water storage tank<\/strong> is located <strong>below ground level<\/strong>.<\/p>\n\n<p class=\"wp-block-paragraph\">Consequently, the only external space occupied is that of <strong>the water treatment plant<\/strong>. This is useful when the goal is to streamline the footprint and create a \u201ccleaner\u201d exterior layout, without altering the reliability of the underlying design. <\/p>\n\n<h2 id=\"quando-la-norma-ammette-il-soprabattente-e-perche-e-una-scelta-di-ripiego\" class=\"wp-block-heading\">When the rules allow for a secondary floor (and why it is a \u201cfallback\u201d option)<\/h2>\n\n<p class=\"wp-block-paragraph\">The same result in terms of overall dimensions can also be achieved by using <strong>horizontal centrifugal pumps<\/strong> with an <strong>ABOVE-FLOW<\/strong> hydraulic configuration. However, this configuration is considered acceptable <strong>only if the two previous UNDERFLOW configurations<\/strong> (centrifugal pumps in underflow or VTP) <strong>could not be used<\/strong>. <\/p>\n\n<p class=\"wp-block-paragraph\">The reasoning given is clear: the status of <strong>\u201cSOPRABATTENTE\u201d<\/strong> is described as \u201ca source of countless problems.\u201d The original text includes a reference to a link for further information, which is not available here: for the full article, it would be best to reinsert it (see the final section, \u201cMissing Data \/ Questions\u201d). <\/p>\n\n<h2 id=\"alimentazioni-idriche-singola-e-singola-superiore-e-accoppiamento-dei-motori\" class=\"wp-block-heading\">Water supplies: single and upper single, and engine coupling<\/h2>\n\n<p class=\"wp-block-paragraph\">Based on the diagrams we&#8217;ve looked at so far, it is shown that it is possible to create:<\/p>\n\n<ul class=\"wp-block-list\">\n<li><strong>Single-type water supply systems<\/strong><\/li>\n\n\n\n<li><strong>Single-point water supply systems<\/strong><\/li>\n<\/ul>\n\n<p class=\"wp-block-paragraph\">In both cases, it is stated that <strong>both electric and diesel<\/strong> engines can be paired with the main pumps. This point is important because it links the choice of pump and hydraulic system to the typical water supply configuration, without limiting the solution to a single type of engine. <\/p>\n\n<h2 id=\"pompe-sommerse-quando-usarle-e-come-giustificarle\" class=\"wp-block-heading\">Submersible Pumps: When to Use Them and How to Justify Their Use<\/h2>\n\n<p class=\"wp-block-paragraph\">The UNI EN 12845 standard requires that <strong>submersible pumps<\/strong> be used <strong>only when strictly necessary<\/strong> and, as indicated, requires that this choice <strong>be justified<\/strong>.<\/p>\n\n<p class=\"wp-block-paragraph\">Specifically, the report must explain why <strong>it was not possible to use<\/strong> the templates with:<\/p>\n\n<ul class=\"wp-block-list\">\n<li><strong>centrifugal pumps<\/strong> (in preferred layouts)<\/li>\n\n\n\n<li><strong>VTP<\/strong><\/li>\n<\/ul>\n\n<p class=\"wp-block-paragraph\">Therefore, submersible pumps are not presented as the \u201cstandard\u201d first option, but rather as a solution to be considered when the most suitable bottom-mounted configurations are not feasible.<\/p>\n\n<h2 id=\"pompe-multistadio-e-axial-split-case-casi-duso-indicati\" class=\"wp-block-heading\">Multistage and Axial Split-Case Pumps: Recommended Applications<\/h2>\n\n<p class=\"wp-block-paragraph\"><strong>Horizontal multistage pumps<\/strong> are described as being designed for systems known as <strong>\u201chigh vertical head\u201d systems<\/strong> (Appendix E). In these cases, the required <strong>head<\/strong> is such that the use of this type of pump is necessary. <\/p>\n\n<p class=\"wp-block-paragraph\">Finally, <strong>axial split-case<\/strong> pumps are recommended for <strong>specific applications<\/strong> where the flow rates of <strong>horizontal centrifugal pumps<\/strong> \u201ctypically\u201d fall short. Here, too, the idea is clear: they are not the \u201cdefault\u201d choice, but rather a solution to client requirements. <\/p>\n\n<h2 id=\"conclusione\" class=\"wp-block-heading\">Conclusion<\/h2>\n\n<p class=\"wp-block-paragraph\">To correctly select the pump types for fire protection water supply systems, the recommended approach is as follows: start with the approved types (UNI EN 12845 and T\/R 11438), prioritize <strong>below-head<\/strong> installation, consider <strong>above-head installation<\/strong> only as an approved alternative when preferable solutions are unavailable, and justify the use of <strong>submersible pumps<\/strong> only when absolutely necessary.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>The UNI EN 12845 standard for fire pumps is the reference when choosing which pumps can be used to supply a fire protection system. Here are the permitted pump types, the recommended hydraulic configurations, and when the standard allows for alternatives. <\/p>\n","protected":false},"featured_media":7870,"parent":0,"template":"","meta":{"_acf_changed":false,"_angie_page":false,"footnotes":"","_members_access_role":[],"_members_access_error":""},"tags":[576,551,569,552,560,574,562,571,549,567],"class_list":["post-7869","esperto-risponde","type-esperto-risponde","status-publish","has-post-thumbnail","hentry","tag-axial-split-case","tag-engineering-insights","tag-fire-protection-water-supply-systems","tag-fire-pumps","tag-lower-sash","tag-multistage-pumps","tag-overhead","tag-submersible-pumps","tag-uni-en-12845","tag-vtp"],"acf":[],"_links":{"self":[{"href":"https:\/\/www.idro-elettrica.it\/en\/wp-json\/wp\/v2\/esperto-risponde\/7869","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.idro-elettrica.it\/en\/wp-json\/wp\/v2\/esperto-risponde"}],"about":[{"href":"https:\/\/www.idro-elettrica.it\/en\/wp-json\/wp\/v2\/types\/esperto-risponde"}],"version-history":[{"count":0,"href":"https:\/\/www.idro-elettrica.it\/en\/wp-json\/wp\/v2\/esperto-risponde\/7869\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.idro-elettrica.it\/en\/wp-json\/wp\/v2\/media\/7870"}],"wp:attachment":[{"href":"https:\/\/www.idro-elettrica.it\/en\/wp-json\/wp\/v2\/media?parent=7869"}],"wp:term":[{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.idro-elettrica.it\/en\/wp-json\/wp\/v2\/tags?post=7869"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}