{"id":670,"date":"2026-10-02T13:17:58","date_gmt":"2026-10-02T11:17:58","guid":{"rendered":"https:\/\/www.valfonta.com\/producto\/safety-valves-for-boilers-jas\/"},"modified":"2026-10-22T09:21:39","modified_gmt":"2026-10-22T07:21:39","slug":"safety-valves-for-boilers-jas","status":"publish","type":"product","link":"https:\/\/www.valfonta.com\/en\/product\/safety-valves-for-boilers-jas\/","title":{"rendered":"JAS safety valves"},"content":{"rendered":"<div class=\"wp-block-group vf-raiz vf-pl-ficha-producto is-layout-flow wp-block-group-is-layout-flow\"><nav class=\"wp-block-group vf-breadcrumbs vfa-aria-label--Breadcrumbs is-layout-flow wp-block-group-is-layout-flow\"><p class=\"vf-envolt wp-block-paragraph\"><a href=\"\/en\/\">Home<\/a><span class=\"vf-sep\" aria-hidden=\"true\">\u203a<\/span><a href=\"https:\/\/www.valfonta.com\/en\/safety-valves\/\">Safety valves<\/a><span class=\"vf-sep\" aria-hidden=\"true\">\u203a<\/span><span aria-current=\"page\">JAS safety valves<\/span><\/p><\/nav><article class=\"wp-block-group vf-pdp vfd-model--JAS is-layout-flow wp-block-group-is-layout-flow\"><div class=\"wp-block-group vf-pdp-hero is-layout-flow wp-block-group-is-layout-flow\"><div class=\"wp-block-group vf-pdp-title is-layout-flow wp-block-group-is-layout-flow\"><p class=\"vf-pdp-eyebrow wp-block-paragraph\">Safety valve \u00b7 Full, instantaneous opening<\/p><h1 class=\"wp-block-heading\">JAS safety valves<\/h1><\/div><div class=\"wp-block-group vf-pdp-media is-layout-flow wp-block-group-is-layout-flow\"><p class=\"vf-envolt wp-block-paragraph\"><span class=\"vf-pdp-badge\">Full opening<\/span><img decoding=\"async\" src=\"https:\/\/www.valfonta.com\/wp-content\/uploads\/2026\/10\/jas-1-700x700-1.jpg\" alt=\"JAS brass safety valve with lever and threaded piped discharge\" class=\"wp-image-195\" width=\"700\" height=\"700\" fetchpriority=\"high\"><\/p><\/div><div class=\"wp-block-group vf-pdp-body is-layout-flow wp-block-group-is-layout-flow\"><p class=\"vf-lead wp-block-paragraph\">Compact full, instantaneous-opening safety valve in brass with a Viton seat. It protects tanks, boilers, and pipes against overpressure and discharges the excess fluid through a piped discharge, without auxiliary power.<\/p><ul class=\"vf-pdp-keys wp-block-list\"><li><span>Sizes<\/span><b>\u00bc\u2033 to \u00be\u2033 <small>inlet<\/small><\/b><\/li><li><span>Opening<\/span><b>Full, instantaneous (A.I.T.)<\/b><\/li><li><span>Maximum pressure<\/span><b>PN16<\/b><\/li><li><span>Max. temperature<\/span><b>180 \u00b0C<\/b><\/li><li><span>Material<\/span><b>Brass \u00b7 Viton seat<\/b><\/li><li><span>Figures<\/span><b>310 with lever \u00b7 311 sealed<\/b><\/li><\/ul><div class=\"wp-block-group vf-pdp-cta is-layout-flow wp-block-group-is-layout-flow\"><p class=\"vf-envolt wp-block-paragraph\"><a class=\"vf-btn vf-btn--pri\" href=\"#solicitar\">Request a quote<\/a><a class=\"vf-btn vf-btn--sec\" href=\"\/wp-content\/uploads\/2026\/10\/JAS.pdf\" target=\"_blank\" rel=\"noopener\">Download datasheet <small>PDF<\/small><\/a><\/p><\/div><p class=\"vf-pdp-contact wp-block-paragraph\">Questions about the set pressure? Call <a href=\"tel:+34933720888\">933 720 888<\/a> or email <a href=\"mailto:valfonta@valfonta.com\">valfonta@valfonta.com<\/a>.<\/p><\/div><\/div><ul class=\"vf-pdp-trust wp-block-list\"><li>Bench-tested under simulated service conditions<\/li><li>Supplied set to the pressure you specify<\/li><li>All components numbered<\/li><li>Material and heat certificates on request<\/li><\/ul><nav class=\"wp-block-group vf-pdp-nav vfa-aria-label--Datasheet%20contents is-layout-flow wp-block-group-is-layout-flow\"><ul class=\"wp-block-list\"><li><a href=\"#aplicaciones\">Applications<\/a><\/li><li><a href=\"#especificaciones\">Specifications<\/a><\/li><li><a href=\"#documentacion\">Documentation<\/a><\/li><li><a href=\"#preguntas\">FAQ<\/a><\/li><li><a href=\"#solicitar\">Request a quote<\/a><\/li><\/ul><\/nav><section id=\"aplicaciones\" class=\"wp-block-group is-layout-flow wp-block-group-is-layout-flow\"><div class=\"wp-block-group vf-pdp-two is-layout-flow wp-block-group-is-layout-flow\"><div class=\"wp-block-group is-layout-flow wp-block-group-is-layout-flow\"><h2 class=\"wp-block-heading\">What the JAS is used for<\/h2><p class=\"wp-block-paragraph\">The <strong>JAS<\/strong> is a full, instantaneous-opening <a href=\"https:\/\/www.valfonta.com\/en\/safety-valves\/\">safety valve<\/a>: it detects excess pressure in tanks, boilers, or pipes and discharges the excess fluid. When the pressure returns to normal, it closes again. It works with liquids, compressed air, inert gases, and steam, and its piped discharge, with a BSP female thread, lets you route the discharge away.<\/p><\/div><aside class=\"wp-block-group vf-pdp-fit is-layout-flow wp-block-group-is-layout-flow\"><h3 class=\"wp-block-heading\">Choose the JAS if\u2026<\/h3><ul class=\"vf-si wp-block-list\"><li>You need a compact, threaded safety valve from \u00bc\u2033 to \u00be\u2033.<\/li><li>The operating pressure does not exceed PN16 and the temperature does not exceed 180 \u00b0C.<\/li><li>You want full, instantaneous opening with piped discharge.<\/li><\/ul><h3 class=\"wp-block-heading\">Choose another model if\u2026<\/h3><ul class=\"vf-no wp-block-list\"><li>You need a larger size, flanges, or stainless steel: see the <a href=\"https:\/\/www.valfonta.com\/en\/product\/alper-fully-open-safety-valve\/\">ALPER<\/a> (up to 4\u2033 or DN100 and 280 \u00b0C).<\/li><li>You prefer progressive opening: see the <a href=\"https:\/\/www.valfonta.com\/en\/product\/progressive-opening-safety-valve\/\">368\u2013371 valve<\/a>.<\/li><\/ul><\/aside><\/div><\/section><section id=\"especificaciones\" class=\"wp-block-group is-layout-flow wp-block-group-is-layout-flow\"><h2 class=\"wp-block-heading\">JAS technical specifications<\/h2><div class=\"wp-block-group vf-tbl-wrap is-layout-flow wp-block-group-is-layout-flow\"><figure class=\"wp-block-table vf-tbl\"><table><tbody><tr><th scope=\"row\">Type<\/th><td>Safety valve with full, instantaneous opening (A.I.T.)<\/td><\/tr><tr><th scope=\"row\">Figures<\/th><td>310: with lever \u00b7 311: sealed<\/td><\/tr><tr><th scope=\"row\">Discharge<\/th><td>Piped<\/td><\/tr><tr><th scope=\"row\">Connections<\/th><td>Inlet: BSP male thread \u00b7 Outlet: BSP female thread<\/td><\/tr><tr><th scope=\"row\">Material<\/th><td>Brass \u00b7 plug with Viton seat<\/td><\/tr><tr><th scope=\"row\">Maximum pressure<\/th><td>PN16<\/td><\/tr><tr><th scope=\"row\">Maximum temperature<\/th><td>180 \u00b0C<\/td><\/tr><tr><th scope=\"row\">Fluids<\/th><td>Liquids, compressed air, inert gases, and steam<\/td><\/tr><tr><th scope=\"row\">Test<\/th><td>On a test bench under simulated service conditions; supplied set to the requested pressure<\/td><\/tr><tr><th scope=\"row\">Certificates<\/th><td>Material, heat, and output certificates, if requested in advance<\/td><\/tr><tr><th scope=\"row\">Other options<\/th><td>AISI 302\/316 stainless steel spring \u00b7 NPT thread<\/td><\/tr><\/tbody><\/table><\/figure><\/div><h3 class=\"wp-block-heading\">Available sizes<\/h3><div class=\"wp-block-group vf-tbl-wrap is-layout-flow wp-block-group-is-layout-flow\"><figure class=\"wp-block-table vf-tbl vf-tbl--grid\"><table><thead><tr><th scope=\"col\">Inlet<\/th><th scope=\"col\">Outlet<\/th><th scope=\"col\">Figure 310<\/th><th scope=\"col\">Figure 311<\/th><\/tr><\/thead><tbody><tr><th scope=\"row\">\u00bc\u2033<\/th><td>3\/8\u2033<\/td><td>Yes<\/td><td>Yes<\/td><\/tr><tr><th scope=\"row\">3\/8\u2033<\/th><td>3\/8\u2033<\/td><td>Yes<\/td><td>Yes<\/td><\/tr><tr><th scope=\"row\">\u00bd\u2033<\/th><td>\u00be\u2033<\/td><td>Yes<\/td><td>Yes<\/td><\/tr><tr><th scope=\"row\">\u00be\u2033<\/th><td>\u00be\u2033<\/td><td>Yes<\/td><td>Yes<\/td><\/tr><\/tbody><\/table><\/figure><\/div><\/section><section id=\"documentacion\" class=\"wp-block-group is-layout-flow wp-block-group-is-layout-flow\"><h2 class=\"wp-block-heading\">JAS technical documentation<\/h2><div class=\"wp-block-group vf-docs is-layout-flow wp-block-group-is-layout-flow\"><div class=\"wp-block-group vf-doc vf-amb-enllac is-layout-flow wp-block-group-is-layout-flow\"><p class=\"vf-envolt wp-block-paragraph\"><i>PDF<\/i><\/p><div class=\"wp-block-group is-layout-flow wp-block-group-is-layout-flow\"><p class=\"vf-envolt wp-block-paragraph\"><b>JAS datasheet<\/b><span>PDF \u00b7 1 page \u00b7 features, figures, and sizes<\/span><\/p><\/div><p class=\"vf-enllac wp-block-paragraph\"><a class=\"vf-enllac-estirat\" href=\"\/wp-content\/uploads\/2026\/10\/JAS.pdf\" aria-label=\"PDF JAS datasheet PDF \u00b7 1 page \u00b7 features, figures, and sizes\" target=\"_blank\" rel=\"noopener\"><\/a><\/p><\/div><\/div><\/section><section id=\"preguntas\" class=\"wp-block-group is-layout-flow wp-block-group-is-layout-flow\"><h2 class=\"wp-block-heading\">Frequently asked questions about the JAS<\/h2><details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary>What is the difference between figure 310 and figure 311?<\/summary><div class=\"wp-block-group is-layout-flow wp-block-group-is-layout-flow\"><p class=\"wp-block-paragraph\">Figure 310 has a lever that allows the valve to be operated manually. The 311 is the sealed version, with no manual operation.<\/p><\/div><\/details><details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary>Is it supplied preset?<\/summary><div class=\"wp-block-group is-layout-flow wp-block-group-is-layout-flow\"><p class=\"wp-block-paragraph\">Yes. Each valve is bench-tested under simulated service conditions and supplied set to the pressure specified by the customer.<\/p><\/div><\/details><details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary>What fluids can it handle?<\/summary><div class=\"wp-block-group is-layout-flow wp-block-group-is-layout-flow\"><p class=\"wp-block-paragraph\">Liquids, compressed air, inert gases, and steam, up to 180 \u00b0C and PN16.<\/p><\/div><\/details><\/section><section id=\"relacionados\" class=\"wp-block-group is-layout-flow wp-block-group-is-layout-flow\"><h2 class=\"wp-block-heading\">Other Valfonta safety valves<\/h2><ul class=\"vf-rel wp-block-list\"><li><a href=\"https:\/\/www.valfonta.com\/en\/product\/alper-fully-open-safety-valve\/\"><img decoding=\"async\" src=\"https:\/\/www.valfonta.com\/wp-content\/uploads\/2026\/10\/alper-1.jpg\" alt=\"ALPER safety valve\" class=\"wp-image-165\" width=\"300\" height=\"300\" loading=\"lazy\"><b>ALPER safety valve<\/b><span>Also full-opening, up to 4\u2033 or DN100, PN25, and 280 \u00b0C.<\/span><\/a><\/li><li><a href=\"https:\/\/www.valfonta.com\/en\/product\/progressive-opening-safety-valve\/\"><img decoding=\"async\" src=\"https:\/\/www.valfonta.com\/wp-content\/uploads\/2026\/10\/alivio-368-700x700-1.jpg\" alt=\"368\u2013371 safety valve\" class=\"wp-image-196\" width=\"300\" height=\"300\" loading=\"lazy\"><b>368\u2013371 safety valve<\/b><span>Progressive opening, from 3\/8\u2033 to 3\u2033 and up to 180 \u00b0C.<\/span><\/a><\/li><li><a href=\"https:\/\/www.valfonta.com\/en\/product\/alper-atmospheric-valves\/\"><img decoding=\"async\" src=\"https:\/\/www.valfonta.com\/wp-content\/uploads\/2026\/10\/alperatmos-2.jpg\" alt=\"ALPER atmospheric valves\" class=\"wp-image-212\" width=\"300\" height=\"300\" loading=\"lazy\"><b>ALPER atmospheric valves<\/b><span>Tank protection against vacuum and overpressure.<\/span><\/a><\/li><li><a href=\"https:\/\/www.valfonta.com\/en\/pressure-relief-valve\/\"><img decoding=\"async\" src=\"https:\/\/www.valfonta.com\/wp-content\/uploads\/2026\/10\/valvula-alivio-presion-s3-s4-perspectiva-400.webp\" alt=\"Pressure relief valves\" class=\"wp-image-10230\" width=\"300\" height=\"300\" loading=\"lazy\"><b>Pressure relief valves<\/b><span>S1\u2013S4 and PRV53\u201355 range, from DN15 to DN150 and set pressure up to 20 barg.<\/span><\/a><\/li><\/ul><\/section><section id=\"solicitar\" class=\"wp-block-group is-layout-flow wp-block-group-is-layout-flow\"><div class=\"wp-block-group vf-quote is-layout-flow wp-block-group-is-layout-flow\"><div class=\"wp-block-group is-layout-flow wp-block-group-is-layout-flow\"><h2 class=\"wp-block-heading\">Request a quote for the JAS<\/h2><p class=\"wp-block-paragraph\">Give us your installation details and we will recommend the right size and figure.<\/p><ul class=\"wp-block-list\"><li>Fluid and temperature<\/li><li>Set pressure<\/li><li>Inlet size<\/li><li>With lever (310) or sealed (311)<\/li><\/ul><p class=\"vf-pdp-contact wp-block-paragraph\">You can also call <a href=\"tel:+34933720888\">933 720 888<\/a>.<\/p><\/div>\n<div class=\"wpcf7 no-js\" id=\"wpcf7-f569-o1\" lang=\"en-US\" dir=\"ltr\" data-wpcf7-id=\"569\">\n<div class=\"screen-reader-response\"><p role=\"status\" aria-live=\"polite\" aria-atomic=\"true\"><\/p> <ul><\/ul><\/div>\n<form action=\"\/en\/wp-json\/wp\/v2\/product\/670#wpcf7-f569-o1\" method=\"post\" class=\"wpcf7-form init vf-form wpcf7-acceptance-as-validation\" aria-label=\"Contact form\" novalidate=\"novalidate\" data-status=\"init\" toolname=\"solicitar_oferta\" tooldescription=\"Request a quote from Valfonta for the models on this page (model, size, fluid and pressures); a member of the team will reply.\">\n<fieldset class=\"hidden-fields-container\"><input type=\"hidden\" name=\"_wpcf7\" value=\"569\" \/><input type=\"hidden\" name=\"_wpcf7_version\" value=\"6.2.3\" \/><input type=\"hidden\" name=\"_wpcf7_locale\" value=\"en_US\" \/><input type=\"hidden\" name=\"_wpcf7_unit_tag\" value=\"wpcf7-f569-o1\" \/><input type=\"hidden\" name=\"_wpcf7_container_post\" value=\"0\" \/><input type=\"hidden\" name=\"_wpcf7_posted_data_hash\" value=\"\" \/><input type=\"hidden\" name=\"_vf_t\" value=\"1792698981.41a62ce0b7f0d30f\" \/>\n<\/fieldset>\n<input class=\"wpcf7-form-control wpcf7-hidden\" value=\"JAS\" type=\"hidden\" name=\"modelo\" \/><label>Name *<span class=\"wpcf7-form-control-wrap\" data-name=\"nombre\"><input size=\"40\" maxlength=\"400\" class=\"wpcf7-form-control wpcf7-text wpcf7-validates-as-required\" autocomplete=\"name\" aria-required=\"true\" aria-invalid=\"false\" value=\"\" type=\"text\" name=\"nombre\" \/><\/span><\/label><label>Company<span class=\"wpcf7-form-control-wrap\" data-name=\"empresa\"><input size=\"40\" maxlength=\"400\" class=\"wpcf7-form-control wpcf7-text\" autocomplete=\"organization\" aria-invalid=\"false\" value=\"\" type=\"text\" name=\"empresa\" \/><\/span><\/label><label>Email *<span class=\"wpcf7-form-control-wrap\" data-name=\"email\"><input size=\"40\" maxlength=\"400\" class=\"wpcf7-form-control wpcf7-email wpcf7-validates-as-required wpcf7-text wpcf7-validates-as-email\" autocomplete=\"email\" aria-required=\"true\" aria-invalid=\"false\" value=\"\" type=\"email\" name=\"email\" \/><\/span><\/label><label>Phone<span class=\"wpcf7-form-control-wrap\" data-name=\"telefono\"><input size=\"40\" maxlength=\"400\" class=\"wpcf7-form-control wpcf7-tel wpcf7-text wpcf7-validates-as-tel\" autocomplete=\"tel\" aria-invalid=\"false\" value=\"\" type=\"tel\" name=\"telefono\" \/><\/span><\/label><fieldset><legend>Application data (optional)<\/legend><label>Size<span class=\"wpcf7-form-control-wrap\" data-name=\"dn\"><select class=\"wpcf7-form-control wpcf7-select\" aria-invalid=\"false\" name=\"dn\"><option value=\"\">Select<\/option><option value=\"\u00bc\u2033\">\u00bc\u2033<\/option><option value=\"3\/8\u2033\">3\/8\u2033<\/option><option value=\"\u00bd\u2033\">\u00bd\u2033<\/option><option value=\"\u00be\u2033\">\u00be\u2033<\/option><option value=\"I don&#039;t know\">I don&#039;t know<\/option><\/select><\/span><\/label><label>Fluid<span class=\"wpcf7-form-control-wrap\" data-name=\"fluido\"><input size=\"40\" maxlength=\"400\" class=\"wpcf7-form-control wpcf7-text\" aria-invalid=\"false\" placeholder=\"steam, air, water\u2026\" value=\"\" type=\"text\" name=\"fluido\" \/><\/span><\/label><label>Set pressure (bar)<span class=\"wpcf7-form-control-wrap\" data-name=\"tarado\"><input size=\"40\" maxlength=\"400\" class=\"wpcf7-form-control wpcf7-text\" aria-invalid=\"false\" value=\"\" type=\"text\" name=\"tarado\" \/><\/span><\/label><label>Temperature (\u00b0C)<span class=\"wpcf7-form-control-wrap\" data-name=\"temperatura\"><input size=\"40\" maxlength=\"400\" class=\"wpcf7-form-control wpcf7-text\" aria-invalid=\"false\" value=\"\" type=\"text\" name=\"temperatura\" \/><\/span><\/label><\/fieldset><label class=\"vf-full\">Message<span class=\"wpcf7-form-control-wrap\" data-name=\"mensaje\"><textarea cols=\"40\" rows=\"4\" maxlength=\"2000\" class=\"wpcf7-form-control wpcf7-textarea\" aria-invalid=\"false\" name=\"mensaje\"><\/textarea><\/span><\/label><label class=\"vf-chk vf-full\"><span class=\"wpcf7-form-control-wrap\" data-name=\"privacidad\"><span class=\"wpcf7-form-control wpcf7-acceptance\"><span class=\"wpcf7-list-item\"><input type=\"checkbox\" name=\"privacidad\" value=\"1\" aria-invalid=\"false\" \/><\/span><\/span><\/span> <span>I have read and accept the <a href=\"\/en\/privacy-policy\/\">privacy policy<\/a> *<\/span><\/label><input class=\"wpcf7-form-control wpcf7-submit has-spinner vf-btn vf-btn--pri\" type=\"submit\" value=\"Send request\" \/><span class=\"vf-hp\" aria-hidden=\"true\"><label>Web <input type=\"text\" name=\"vf_web\" value=\"\" tabindex=\"-1\" autocomplete=\"off\" toolparamdescription=\"Campo de control: d\u00e9jalo vac\u00edo\"><\/label><\/span><div class=\"wpcf7-response-output\" aria-hidden=\"true\"><\/div>\n<\/form>\n<\/div>\n\n<\/div><\/section><div class=\"wp-block-group vf-pdp-bar is-layout-flow wp-block-group-is-layout-flow\"><p class=\"vf-envolt wp-block-paragraph\"><a class=\"vf-btn vf-btn--sec\" href=\"tel:+34933720888\">Call<\/a><a class=\"vf-btn vf-btn--pri\" href=\"#solicitar\">Request a quote<\/a><\/p><\/div><\/article><\/div>","protected":false},"excerpt":{"rendered":"<p>Home\u203aSafety valves\u203aJAS safety valves Safety valve \u00b7 Full, instantaneous opening JAS safety valves Full opening Compact full, instantaneous-opening safety valve in brass with a Viton seat. It protects tanks, boilers, and pipes against overpressure and discharges the excess fluid through a piped discharge, without auxiliary power. Request a quoteDownload datasheet PDF Questions about the set ... <a title=\"JAS safety valves\" class=\"read-more\" href=\"https:\/\/www.valfonta.com\/en\/product\/safety-valves-for-boilers-jas\/\" aria-label=\"Read more about JAS safety valves\">Read more<\/a><\/p>\n","protected":false},"featured_media":0,"template":"","meta":{"_acf_changed":false,"_generate-full-width-content":"true","_generate-disable-headline":"true","rank_math_title":"JAS boiler safety valves | Valfonta","rank_math_description":"JAS brass safety valve with full, instantaneous opening and Viton seat. \u00bc\u2033 to \u00be\u2033 inlet, PN16, up to 180 \u00b0C, lever or sealed version.","rank_math_focus_keyword":"","vf_jsonld":"[{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"Organization\",\"@id\":\"https:\/\/www.valfonta.com\/#organization\",\"name\":\"Valfonta\",\"legalName\":\"Val Fonta, S.L.\",\"taxID\":\"B59935718\",\"url\":\"https:\/\/www.valfonta.com\/en\/\",\"logo\":{\"@type\":\"ImageObject\",\"url\":\"https:\/\/www.valfonta.com\/wp-content\/uploads\/2026\/10\/valfonta-logo.webp\"},\"foundingDate\":\"1962\",\"email\":\"valfonta@valfonta.com\",\"telephone\":\"+34 933 720 888\",\"address\":{\"@type\":\"PostalAddress\",\"streetAddress\":\"C\/ Bronze 26, Pol. Ind. Les Guixeres\",\"postalCode\":\"08915\",\"addressLocality\":\"Badalona\",\"addressRegion\":\"Barcelona\",\"addressCountry\":\"ES\"},\"description\":\"Design, manufacture, and sale of pressure reducing valves, pressure relief valves, and control valves.\"},{\"@type\":\"WebSite\",\"@id\":\"https:\/\/www.valfonta.com\/#website\",\"url\":\"https:\/\/www.valfonta.com\/en\/\",\"name\":\"Valfonta\",\"publisher\":{\"@id\":\"https:\/\/www.valfonta.com\/#organization\"},\"inLanguage\":\"en\"},{\"@type\":\"ItemPage\",\"@id\":\"https:\/\/www.valfonta.com\/en\/product\/safety-valves-for-boilers-jas\/#webpage\",\"url\":\"https:\/\/www.valfonta.com\/en\/product\/safety-valves-for-boilers-jas\/\",\"name\":\"JAS boiler safety valves | Valfonta\",\"description\":\"JAS brass safety valve with full, instantaneous opening and Viton seat. \u00bc\u2033 to \u00be\u2033 inlet, PN16, up to 180 \u00b0C, lever or sealed version.\",\"isPartOf\":{\"@id\":\"https:\/\/www.valfonta.com\/#website\"},\"about\":{\"@id\":\"https:\/\/www.valfonta.com\/#organization\"},\"inLanguage\":\"en\",\"datePublished\":\"2020-02-05T13:48:36+02:00\",\"dateModified\":\"2025-12-19T10:48:06+02:00\",\"primaryImageOfPage\":{\"@id\":\"https:\/\/www.valfonta.com\/wp-content\/uploads\/2026\/10\/jas-1-700x700-1.jpg\"},\"breadcrumb\":{\"@id\":\"https:\/\/www.valfonta.com\/en\/product\/safety-valves-for-boilers-jas\/#breadcrumb\"},\"mainEntity\":{\"@id\":\"https:\/\/www.valfonta.com\/en\/product\/safety-valves-for-boilers-jas\/#product\"}},{\"@type\":\"ImageObject\",\"@id\":\"https:\/\/www.valfonta.com\/wp-content\/uploads\/2026\/10\/jas-1-700x700-1.jpg\",\"url\":\"https:\/\/www.valfonta.com\/wp-content\/uploads\/2026\/10\/jas-1-700x700-1.jpg\",\"width\":\"1000\",\"height\":\"1000\",\"caption\":\"Safety valve\",\"inLanguage\":\"en\"},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\/\/www.valfonta.com\/en\/product\/safety-valves-for-boilers-jas\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\/\/www.valfonta.com\/en\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Safety valves\",\"item\":\"https:\/\/www.valfonta.com\/en\/safety-valves\/\"},{\"@type\":\"ListItem\",\"position\":3,\"name\":\"JAS safety valves\",\"item\":\"https:\/\/www.valfonta.com\/en\/product\/safety-valves-for-boilers-jas\/\"}]},{\"@type\":\"Product\",\"@id\":\"https:\/\/www.valfonta.com\/en\/product\/safety-valves-for-boilers-jas\/#product\",\"name\":\"JAS safety valves\",\"url\":\"https:\/\/www.valfonta.com\/en\/product\/safety-valves-for-boilers-jas\/\",\"description\":\"Compact full, instantaneous-opening safety valve in brass with a Viton seat. It protects tanks, boilers, and pipes against overpressure and discharges the excess fluid through a piped discharge, without auxiliary power.\",\"brand\":{\"@type\":\"Brand\",\"name\":\"Valfonta\"},\"manufacturer\":{\"@id\":\"https:\/\/www.valfonta.com\/#organization\"},\"model\":\"JAS\",\"image\":\"https:\/\/www.valfonta.com\/wp-content\/uploads\/2026\/10\/jas-1-700x700-1.jpg\",\"material\":\"Brass\",\"additionalProperty\":[{\"@type\":\"PropertyValue\",\"name\":\"Type\",\"value\":\"Safety valve with full, instantaneous opening (A.I.T.)\"},{\"@type\":\"PropertyValue\",\"name\":\"Figures\",\"value\":\"310: with lever \u00b7 311: sealed\"},{\"@type\":\"PropertyValue\",\"name\":\"Discharge\",\"value\":\"Piped\"},{\"@type\":\"PropertyValue\",\"name\":\"Connections\",\"value\":\"Inlet: BSP male thread \u00b7 Outlet: BSP female thread\"},{\"@type\":\"PropertyValue\",\"name\":\"Material\",\"value\":\"Brass \u00b7 plug with Viton seat\"},{\"@type\":\"PropertyValue\",\"name\":\"Maximum pressure\",\"value\":\"PN16\"},{\"@type\":\"PropertyValue\",\"name\":\"Maximum temperature\",\"value\":\"180 \u00b0C\"},{\"@type\":\"PropertyValue\",\"name\":\"Fluids\",\"value\":\"Liquids, compressed air, inert gases, and steam\"},{\"@type\":\"PropertyValue\",\"name\":\"Test\",\"value\":\"On a test bench under simulated service conditions; supplied set to the requested pressure\"},{\"@type\":\"PropertyValue\",\"name\":\"Certificates\",\"value\":\"Material, heat, and output certificates, if requested in advance\"},{\"@type\":\"PropertyValue\",\"name\":\"Other options\",\"value\":\"AISI 302\/316 stainless steel spring \u00b7 NPT thread\"}],\"category\":\"Safety valves\",\"subjectOf\":[{\"@type\":\"DigitalDocument\",\"name\":\"JAS datasheet\",\"url\":\"https:\/\/www.valfonta.com\/wp-content\/uploads\/2026\/10\/JAS.pdf\",\"encodingFormat\":\"application\/pdf\"}]},{\"@type\":\"FAQPage\",\"@id\":\"https:\/\/www.valfonta.com\/en\/product\/safety-valves-for-boilers-jas\/#faq\",\"mainEntity\":[{\"@type\":\"Question\",\"name\":\"What is the difference between figure 310 and figure 311?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Figure 310 has a lever that allows the valve to be operated manually. The 311 is the sealed version, with no manual operation.\"}},{\"@type\":\"Question\",\"name\":\"Is it supplied preset?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Yes. Each valve is bench-tested under simulated service conditions and supplied set to the pressure specified by the customer.\"}},{\"@type\":\"Question\",\"name\":\"What fluids can it handle?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Liquids, compressed air, inert gases, and steam, up to 180 \u00b0C and PN16.\"}}]}]}]"},"product_brand":[],"product_cat":[79],"product_tag":[],"class_list":["post-670","product","type-product","status-publish","product_cat-sin-categorizar","first","instock","shipping-taxable","product-type-simple"],"acf":[],"_links":{"self":[{"href":"https:\/\/www.valfonta.com\/en\/wp-json\/wp\/v2\/product\/670","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.valfonta.com\/en\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/www.valfonta.com\/en\/wp-json\/wp\/v2\/types\/product"}],"wp:attachment":[{"href":"https:\/\/www.valfonta.com\/en\/wp-json\/wp\/v2\/media?parent=670"}],"wp:term":[{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/www.valfonta.com\/en\/wp-json\/wp\/v2\/product_brand?post=670"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/www.valfonta.com\/en\/wp-json\/wp\/v2\/product_cat?post=670"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/www.valfonta.com\/en\/wp-json\/wp\/v2\/product_tag?post=670"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}