{"title":"Boiler Fill Valves \u0026 Feed Valves","description":"\u003cp\u003eA boiler fill valve (also called a boiler feed valve or pressure reducing valve) keeps a hydronic heating system at the right cold-fill pressure, usually 12 to 15 psi for a typical two-story home. It automatically adds make-up water when pressure drops and lets you fast-fill the system after service. If your boiler pressure keeps falling, the fill valve never shuts off, or the relief valve drips, a worn or clogged fill valve is a common cause.\u003c\/p\u003e\u003cp\u003eThis collection lists fill and feed valves by part number, including \u003cstrong\u003eCaleffi AutoFill\u003c\/strong\u003e 553 and 573 series (with or without gauge, NPT, sweat and press connections), the \u003cstrong\u003eCaleffi 573\/574 COMBO\u003c\/strong\u003e models with a built-in backflow preventer, \u003cstrong\u003eResideo NK300S\u003c\/strong\u003e and \u003cstrong\u003eFM911\u003c\/strong\u003e feed valve and backflow combinations, and \u003cstrong\u003eTaco 329\u003c\/strong\u003e fast-fill and \u003cstrong\u003e335\u003c\/strong\u003e boiler feed valves. Replacement cartridges are listed where available.\u003c\/p\u003e\u003cp\u003eMany local codes require a backflow preventer on the boiler fill line. A combination valve saves space and two joints. Match the inlet and outlet size (1\/2\" or 3\/4\"), connection type and pressure range to your system, and check whether your boiler needs an ASSE 1012 or 1013 backflow device.\u003c\/p\u003e\u003cp\u003eShop the rest of the hydronic water side in \u003ca href=\"\/collections\/boiler-parts\"\u003eBoiler Parts\u003c\/a\u003e, or go straight to \u003ca href=\"\/collections\/relief-valves\"\u003erelief valves\u003c\/a\u003e, \u003ca href=\"\/collections\/expansion-tanks-heating\"\u003eexpansion tanks\u003c\/a\u003e, \u003ca href=\"\/collections\/backflow-preventers\"\u003ebackflow preventers\u003c\/a\u003e and \u003ca href=\"\/collections\/system-fill-tanks-autofills\"\u003esystem fill tanks\u003c\/a\u003e.\u003c\/p\u003e","products":[{"product_id":"auto-fill-boiler-feed-valve1-2npt-inlet","title":"Caleffi North America 553542A Auto Fill Boiler Feed Valve1\/2\"NPT Inlet","description":"\u003cp\u003eThe Auto fill Boiler Feed Valve1\/2\"NPT Inlet by Caleffi North America is part of our system fill tanks \u0026amp; autofills selection.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Caleffi North America\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part #:\u003c\/strong\u003e 553542A\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 8016615073072\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCategory:\u003c\/strong\u003e System Fill Tanks \u0026amp; Autofills\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Caleffi","offers":[{"title":"Default Title","offer_id":44350383095911,"sku":"CALE-553542A","price":115.59,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0651\/2253\/3479\/files\/553542A_CALE-553542A_8016615073072.jpg?v=1785803304"},{"product_id":"autofill-1-2sweat-inlet-x-1-2-npt-outlet","title":"Caleffi North America 553549A AutoFill™ 1\/2\"Sweat Inlet X 1\/2\" NPT Outlet","description":"\u003cp\u003eThe AutoFill™ 1\/2\"Sweat Inlet X 1\/2\" NPT outlet by Caleffi North America is part of our system fill tanks \u0026amp; autofills selection.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Caleffi North America\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part #:\u003c\/strong\u003e 553549A\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 8016615962123\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCategory:\u003c\/strong\u003e System Fill Tanks \u0026amp; Autofills\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Caleffi","offers":[{"title":"Default Title","offer_id":44350383161447,"sku":"CALE-553549A","price":106.33,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0651\/2253\/3479\/files\/553549A_CALE-553549A_8016615962123.jpg?v=1785803306"},{"product_id":"autofill-1-2-npt-inlet-x-1-2-npt-outlet-w-pressure-gauge","title":"Caleffi North America 553642A AutoFill™ 1\/2\" NPT Inlet X 1\/2\" NPT Outlet w\/ Pressure Gauge","description":"\u003cp\u003eThe AutoFill™ 1\/2\" NPT Inlet X 1\/2\" NPT Outlet w\/ Pressure Gauge by Caleffi North America is part of our system fill tanks \u0026amp; autofills selection.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Caleffi North America\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part #:\u003c\/strong\u003e 553642A\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 8016615504927\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCategory:\u003c\/strong\u003e System Fill Tanks \u0026amp; Autofills\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Caleffi","offers":[{"title":"Default Title","offer_id":44350383226983,"sku":"CALE-553642A","price":128.19,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0651\/2253\/3479\/files\/553642A_CALE-553642A_8016615504927.jpg?v=1785803307"},{"product_id":"autofill-1-2sweat-inlet-x-1-2-npt-outlet-w-pressure-gauge","title":"Caleffi North America 553649A AutoFill™ 1\/2\"Sweat Inlet X 1\/2\" NPT Outlet w\/ Pressure Gauge","description":"\u003cp\u003eThe AutoFill™ 1\/2\"Sweat Inlet X 1\/2\" NPT outlet w\/ Pressure Gauge by Caleffi North America is part of our system fill tanks \u0026amp; autofills selection.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Caleffi North America\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part #:\u003c\/strong\u003e 553649A\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 8016615504941\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCategory:\u003c\/strong\u003e System Fill Tanks \u0026amp; Autofills\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Caleffi","offers":[{"title":"Default Title","offer_id":44350383358055,"sku":"CALE-553649A","price":136.67,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0651\/2253\/3479\/files\/553649A_CALE-553649A_8016615504941.jpg?v=1785803309"},{"product_id":"combo-autofill-1-2-sweat-inlet-x-1-2-npt-outlet-asse-1012","title":"Caleffi North America 573009A COMBO AutoFill™ 1\/2\" Sweat Inlet X 1\/2\" NPT Outlet ASSE 1012","description":"\u003cp\u003eThe COMBO AutoFill™ 1\/2\" Sweat Inlet X 1\/2\" NPT Outlet ASSE 1012 by Caleffi North America is part of our system fill tanks \u0026amp; autofills selection.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Caleffi North America\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part #:\u003c\/strong\u003e 573009A\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 8016615962017\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCategory:\u003c\/strong\u003e System Fill Tanks \u0026amp; Autofills\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Caleffi","offers":[{"title":"Default Title","offer_id":44350383423591,"sku":"CALE-573009A","price":207.51,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0651\/2253\/3479\/files\/573009A_CALE-573009A_8016615962017.jpg?v=1785803309"},{"product_id":"autofill-replacement-cartridge","title":"Caleffi North America F59650 Autofill Replacement Cartridge","description":"\u003cp\u003eThe Autofill Replacement Cartridge by Caleffi North America is part of our mixing valve accessories \u0026amp; parts selection.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Caleffi North America\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part #:\u003c\/strong\u003e F59650\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 8016615105391\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCategory:\u003c\/strong\u003e Mixing Valve Accessories \u0026amp; Parts\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Caleffi","offers":[{"title":"Default Title","offer_id":44350383620199,"sku":"CALE-F59650","price":34.09,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0651\/2253\/3479\/files\/F59650_CALE-F59650_8016615105391.jpg?v=1785803313"},{"product_id":"combination-boiler-feed-valve-with-sweat-and-threaded-connections","title":"Resideo NK300S-100 Combination Boiler Feed Valve with Sweat and Threaded Connections","description":"\u003cp\u003eThe NK300S-100 is a combination boiler feed valve from Resideo (Honeywell Home), 1\/2 in, sweat and threaded connections.\u003c\/p\u003e\u003cp\u003eFilling a boiler needs four things in the same line: a shutoff, a backflow preventer so system water can never reach the potable supply, a pressure reducing valve so the fill stops at system pressure instead of at street pressure, and a strainer. A combination valve is all of it in one body, which is fewer joints to make and fewer joints to leak.\u003c\/p\u003e\u003cp\u003eThe \u003cstrong\u003ebackflow preventer is the part that is not optional\u003c\/strong\u003e. Boiler water is treated water sitting against steel; the code separation between it and the drinking supply is the whole reason this assembly exists in this form.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eFast fill\u003c\/strong\u003e means it can be opened wide to charge a dry system quickly and then returned to regulating, instead of taking an afternoon to fill through a reducing valve at its setpoint.\u003c\/p\u003e\u003cp\u003eWhat is in the body: boiler fill shut off valve, double check backflow preventer with air vent and discharge connection, valve cartridge, integrated 200 micron strainer, a check valve, pressure reducing valve with valve insert, adjustment spring, and pressure gauge.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Resideo (Honeywell Home)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part #:\u003c\/strong\u003e NK300S-100\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eType:\u003c\/strong\u003e Combination boiler feed valve\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePipe size:\u003c\/strong\u003e 1\/2 in\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eConnection:\u003c\/strong\u003e Includes sweat and threaded connections\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eValve type:\u003c\/strong\u003e Fast Fill\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eClose-off pressure:\u003c\/strong\u003e 14.5 psi minimum (inlet to outlet)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaximum fluid temperature:\u003c\/strong\u003e 180 F\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBody material:\u003c\/strong\u003e Brass\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaximum pressure:\u003c\/strong\u003e 150 psi\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIncludes:\u003c\/strong\u003e Boiler fill shut off valve, double check backflow preventer with air vent and discharge connection, valve cartridge, integrated 200 micron strainer, a check valve, pressure reducing valve with valve insert, adjustment spring, and pressure gauge\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 085267561389\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eShipping weight:\u003c\/strong\u003e 3.96 lb\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCategory:\u003c\/strong\u003e Boiler Fill Valves\u003c\/li\u003e\n\u003c\/ul\u003e\u003cdiv class=\"ths-mfr-data\"\u003e\n\u003ch3\u003eFull Specifications\u003c\/h3\u003e\n\u003ctable class=\"ths-spec-table\"\u003e\u003ctbody\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eApplication\u003c\/th\u003e\n\u003ctd\u003eClosed-loop Heating Systems\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eProduct Features\u003c\/th\u003e\n\u003ctd\u003eOptimal protection of the potable water supply system, Pressure reducing valve with inlet pressure balancing - inlet pressure fluctuation does not influence the outlet pressure, Outlet pressure adjustable and directly visible on the pressure gaug, Low maintenance effort - cartridge insert and valve insert are completely replaceable, Pressure Gauge: 0-60 psi @ max temp 140°F (60°C)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eValve Type\u003c\/th\u003e\n\u003ctd\u003ePressure Reducing Valve\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eControlled Media\u003c\/th\u003e\n\u003ctd\u003eDrinking Water\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eDN Size\u003c\/th\u003e\n\u003ctd\u003e1\/2 in\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eFor Use With\u003c\/th\u003e\n\u003ctd\u003eS06K-1\/4NPT Blanking Plug\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eIncludes\u003c\/th\u003e\n\u003ctd\u003eBoiler fill shut off valve, Valve cartridge, Integrated 200 micron strainer, Check valve, Pressure reducing valve with valve insert, Adjustment spring, Pressure gauge, Double check backflow preventer with air vent and discharge connection\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eCompatible With\u003c\/th\u003e\n\u003ctd\u003eResidential Boilers, Light Commercial Boilers, Multi-Family Residential Boilers\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eWarranty\u003c\/th\u003e\n\u003ctd\u003e5 years\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eApprovals and Standards\u003c\/th\u003e\n\u003ctd\u003eASSE 1081 Listed\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eMedia Temperature (Max)\u003c\/th\u003e\n\u003ctd\u003e180 F, 82 C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eOperating Pressure (Max)\u003c\/th\u003e\n\u003ctd\u003e58 psi\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eOutlet Pressure (Min)\u003c\/th\u003e\n\u003ctd\u003e10 psi, 0.7 bar\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eOutlet Pressure (Max)\u003c\/th\u003e\n\u003ctd\u003e58 psi, 4.0 bar\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eInlet Pressure (Min)\u003c\/th\u003e\n\u003ctd\u003e30 psi, 2.0 bar\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eInlet Pressure (Max)\u003c\/th\u003e\n\u003ctd\u003e150 psi, 10.3 bar\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eFlow Rate (Max)\u003c\/th\u003e\n\u003ctd\u003e16 gpm @ 22 psi, 60 l\/min @ 1.5 bar\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eMounting Position\u003c\/th\u003e\n\u003ctd\u003eHorizontal pipework with discharge connection directed downwards\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eColor\u003c\/th\u003e\n\u003ctd\u003eBrass, Black, Red, White\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eValve Diaphragm Material\u003c\/th\u003e\n\u003ctd\u003eEPDM, Fabric-reinforced diaphragm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eValve Spring Material\u003c\/th\u003e\n\u003ctd\u003eSteel\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eSeal Material\u003c\/th\u003e\n\u003ctd\u003eEPDM Rubber, NBR\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eFilter Material\u003c\/th\u003e\n\u003ctd\u003eStainless steel fine mesh\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eAmbient Operating Temperature (Min)\u003c\/th\u003e\n\u003ctd\u003e33 °F, 1 °C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eAmbient Operating Temperature (Max)\u003c\/th\u003e\n\u003ctd\u003e140 °F, 60 °C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eProduct Height\u003c\/th\u003e\n\u003ctd\u003e7.48 in, 190 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eProduct Length\u003c\/th\u003e\n\u003ctd\u003e7.79 in, 198 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eProduct Weight\u003c\/th\u003e\n\u003ctd\u003e1.8 kg, 4 lb\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eAdditional Dimensions Details\u003c\/th\u003e\n\u003ctd\u003eConnection size discharge: 1\/2 in NPT, Connection size test ports: 1\/4 in NPT\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\u003c\/table\u003e\n\u003ch3\u003eDocuments \u0026amp; Downloads\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/digitalassets.resideo.com\/damroot\/Original\/10018\/nk300s-pd-en0h1556ge23.pdf\" target=\"_blank\" rel=\"noopener\"\u003eBraukmann NK300S Product Specification (English)\u003c\/a\u003e (1.9MB PDF)\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/digitalassets.resideo.com\/damroot\/Original\/10014\/33-00339EFS.pdf\" target=\"_blank\" rel=\"noopener\"\u003eInstallation Instructions for NK300S Boiler Feed Combination (English, French, Spanish)\u003c\/a\u003e (2.1MB PDF)\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/digitalassets.resideo.com\/damroot\/Original\/10000\/03-00563.pdf\" target=\"_blank\" rel=\"noopener\"\u003eBrochure for the Hydronic Products with Press Fittings (English)\u003c\/a\u003e (9.4MB PDF)\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/digitalassets.resideo.com\/damroot\/Original\/10014\/03-00392.pdf\" target=\"_blank\" rel=\"noopener\"\u003eSell Sheet for NK300S Boiler Feed Combination Valve (English)\u003c\/a\u003e (1.0MB PDF)\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/digitalassets.resideo.com\/damroot\/Original\/10005\/33-00321.pdf\" target=\"_blank\" rel=\"noopener\"\u003eSubmittal Sheet for NK300S Boiler Feed Combination (English)\u003c\/a\u003e (0.1MB PDF)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e","brand":"Resideo","offers":[{"title":"Default Title","offer_id":44351319408743,"sku":"HONE-NK300S-100","price":261.3,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0651\/2253\/3479\/files\/NK300S-c4-6.jpg?v=1785815826"},{"product_id":"combination-boiler-feed-valve-with-union-press-fitting-connections","title":"Resideo NK300S-100UP Combination Boiler Feed Valve with Union Press Fitting Connections","description":"\u003cp\u003eThe NK300S-100UP is a combination boiler feed valve from Resideo (Honeywell Home), 1\/2 in, union press connections.\u003c\/p\u003e\u003cp\u003eFilling a boiler needs four things in the same line: a shutoff, a backflow preventer so system water can never reach the potable supply, a pressure reducing valve so the fill stops at system pressure instead of at street pressure, and a strainer. A combination valve is all of it in one body, which is fewer joints to make and fewer joints to leak.\u003c\/p\u003e\u003cp\u003eThe \u003cstrong\u003ebackflow preventer is the part that is not optional\u003c\/strong\u003e. Boiler water is treated water sitting against steel; the code separation between it and the drinking supply is the whole reason this assembly exists in this form.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eFast fill\u003c\/strong\u003e means it can be opened wide to charge a dry system quickly and then returned to regulating, instead of taking an afternoon to fill through a reducing valve at its setpoint.\u003c\/p\u003e\u003cp\u003eWhat is in the body: boiler fill shut off valve, double check backflow preventer with air vent and discharge connection, valve cartridge, integrated 200 micron strainer, a check valve, pressure reducing valve with valve insert, adjustment spring, and pressure gauge.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Resideo (Honeywell Home)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part #:\u003c\/strong\u003e NK300S-100UP\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eType:\u003c\/strong\u003e Combination boiler feed valve\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePipe size:\u003c\/strong\u003e 1\/2 in\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eConnection:\u003c\/strong\u003e Includes union press fitting connections\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eValve type:\u003c\/strong\u003e Fast Fill\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eClose-off pressure:\u003c\/strong\u003e 14.5 psi minimum (inlet to outlet)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaximum fluid temperature:\u003c\/strong\u003e 180 F\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBody material:\u003c\/strong\u003e Brass\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaximum pressure:\u003c\/strong\u003e 150 psi\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIncludes:\u003c\/strong\u003e Boiler fill shut off valve, double check backflow preventer with air vent and discharge connection, valve cartridge, integrated 200 micron strainer, a check valve, pressure reducing valve with valve insert, adjustment spring, and pressure gauge\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 085267345163\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCategory:\u003c\/strong\u003e Boiler Fill Valves\u003c\/li\u003e\n\u003c\/ul\u003e\u003cdiv class=\"ths-mfr-data\"\u003e\n\u003ch3\u003eFull Specifications\u003c\/h3\u003e\n\u003ctable class=\"ths-spec-table\"\u003e\u003ctbody\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eApplication\u003c\/th\u003e\n\u003ctd\u003eClosed-loop Heating Systems\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eProduct Features\u003c\/th\u003e\n\u003ctd\u003e Conveniently located test ports for easy inspections and check out, Optimal protection of the potable water supply system, Pressure reducing valve with inlet pressure balancing - inlet pressure fluctuation does not influence the outlet pressure, Outlet pressure adjustable and directly visible on the pressure gauge, Low maintenance effort - cartridge insert and valve insert are completely replaceable, Pressure Gauge: 0-60 psi @ max temp 140°F (60°C)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eControlled Media\u003c\/th\u003e\n\u003ctd\u003eDrinking Water\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eDN Size\u003c\/th\u003e\n\u003ctd\u003e1\/2 in\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eFor Use With\u003c\/th\u003e\n\u003ctd\u003eS06K-1\/4NPT Blanking Plug\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eIncludes\u003c\/th\u003e\n\u003ctd\u003eBoiler fill shut off valve, Double check backflow preventer with air vent and discharge connection, Valve cartridge, Integrated 200 micron strainer, Check valve, Pressure reducing valve with valve insert, Adjustment spring\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eCompatible With\u003c\/th\u003e\n\u003ctd\u003eResidential Boilers, Light Commercial Boilers, Multi-Family Residential Boilers\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eWarranty\u003c\/th\u003e\n\u003ctd\u003e5 years\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eApprovals and Standards\u003c\/th\u003e\n\u003ctd\u003eASSE 1081 Listed\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eMedia Temperature (Max)\u003c\/th\u003e\n\u003ctd\u003e180 °F, 82 °C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eOutlet Pressure (Min)\u003c\/th\u003e\n\u003ctd\u003e10 psi, 0.7 bar\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eOutlet Pressure (Max)\u003c\/th\u003e\n\u003ctd\u003e58 psi, 4.0 bar\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eInlet Pressure (Min)\u003c\/th\u003e\n\u003ctd\u003e30 psi, 2.0 bar\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eInlet Pressure (Max)\u003c\/th\u003e\n\u003ctd\u003e150 psi, 10.3 bar\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003ePreset Outlet Pressure\u003c\/th\u003e\n\u003ctd\u003eFactory set 15 psi, Factory set 1 bar\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eFlow Rate (Max)\u003c\/th\u003e\n\u003ctd\u003e16 gpm @ 22 psi, 60 l\/min @ 1.5 bar\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eMounting Position\u003c\/th\u003e\n\u003ctd\u003eHorizontal pipework with discharge connection directed downwards\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eColor\u003c\/th\u003e\n\u003ctd\u003eBrass, Black, Red, White\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eValve Diaphragm Material\u003c\/th\u003e\n\u003ctd\u003eEPDM\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eValve Spring Material\u003c\/th\u003e\n\u003ctd\u003eStainless Steel\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eSeal Material\u003c\/th\u003e\n\u003ctd\u003eEPDM Rubber, NBR\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eFilter Material\u003c\/th\u003e\n\u003ctd\u003eStainless steel fine mesh\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eAmbient Operating Temperature (Min)\u003c\/th\u003e\n\u003ctd\u003e33 °F, 1 °C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eAmbient Operating Temperature (Max)\u003c\/th\u003e\n\u003ctd\u003e140 °F, 60 °C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eFilter Size\u003c\/th\u003e\n\u003ctd\u003e200 micron\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eProduct Height\u003c\/th\u003e\n\u003ctd\u003e7.48 in, 190 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eProduct Length\u003c\/th\u003e\n\u003ctd\u003e7.79 in, 198 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eProduct Weight\u003c\/th\u003e\n\u003ctd\u003e1.8 kg, 4 lb\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\u003c\/table\u003e\n\u003ch3\u003eDocuments \u0026amp; Downloads\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/digitalassets.resideo.com\/damroot\/Original\/10018\/nk300s-pd-en0h1556ge23.pdf\" target=\"_blank\" rel=\"noopener\"\u003eBraukmann NK300S Product Specification (English)\u003c\/a\u003e (1.9MB PDF)\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/digitalassets.resideo.com\/damroot\/Original\/10014\/33-00339EFS.pdf\" target=\"_blank\" rel=\"noopener\"\u003eInstallation Instructions for NK300S Boiler Feed Combination (English, French, Spanish)\u003c\/a\u003e (2.1MB PDF)\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/digitalassets.resideo.com\/damroot\/Original\/10000\/03-00563.pdf\" target=\"_blank\" rel=\"noopener\"\u003eBrochure for the Hydronic Products with Press Fittings (English)\u003c\/a\u003e (9.4MB PDF)\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/digitalassets.resideo.com\/damroot\/Original\/10014\/03-00392.pdf\" target=\"_blank\" rel=\"noopener\"\u003eSell Sheet for NK300S Boiler Feed Combination Valve (English)\u003c\/a\u003e (1.0MB PDF)\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/digitalassets.resideo.com\/damroot\/Original\/10005\/33-00321.pdf\" target=\"_blank\" rel=\"noopener\"\u003eSubmittal Sheet for NK300S Boiler Feed Combination (English)\u003c\/a\u003e (0.1MB PDF)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e","brand":"Resideo","offers":[{"title":"Default Title","offer_id":44351319441511,"sku":"HONE-NK300S-100UP","price":285.04,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0651\/2253\/3479\/files\/NK300S-100UP-c5-6.jpg?v=1785815827"},{"product_id":"boiler-feed-valve-1-2-fast-fill","title":"Taco Comfort Solutions 329-3 BOILER FEED VALVE - 1\/2\" Fast Fill","description":"\u003cp\u003eTaco Comfort Solutions 329-3 is the Boiler Feed Valve - 1\/2\" Fast Fill.\u003c\/p\u003e\u003cp\u003eThis boiler feed valve reduces incoming water pressure and automatically maintains fill pressure in a closed hydronic heating system. The fast fill feature allows quick filling and purging of the system during startup and service.\u003c\/p\u003e\u003cp\u003eConfirm the 1\/2\" connection style before installation. Install it in the cold water make-up line with a backflow preventer where local code requires one, and set the fill pressure to suit the height of the system.\u003c\/p\u003e\u003ch3\u003eSpecifications\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Taco Comfort Solutions\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part #:\u003c\/strong\u003e 329-3\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSize:\u003c\/strong\u003e 1\/2\"\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 687752022247\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCategory:\u003c\/strong\u003e System Fill Tanks \u0026amp; Autofills\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eSee also: \u003ca href=\"\/collections\/system-fill-tanks-autofills\"\u003eSystem Fill Tanks \u0026amp; Autofills\u003c\/a\u003e, \u003ca href=\"\/collections\/expansion-tanks-heating\"\u003eHeating Expansion Tanks\u003c\/a\u003e, \u003ca href=\"\/collections\/taco-comfort-solutions\"\u003eTaco Comfort Solutions\u003c\/a\u003e, \u003ca href=\"\/collections\/heating\"\u003eHeating\u003c\/a\u003e\u003c\/p\u003e","brand":"Taco Comfort Solutions","offers":[{"title":"Default Title","offer_id":44353379729511,"sku":"TACO-329-3","price":125.67,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0651\/2253\/3479\/files\/Taco_329-2.png?v=1785831907"},{"product_id":"boiler-feed-valve-1-2-threaded-fast-fill","title":"Taco Comfort Solutions 329-T3 BOILER FEED VALVE - 1\/2\" Threaded Fast Fill","description":"\u003cp\u003eTaco Comfort Solutions 329-T3 is the Boiler Feed Valve - 1\/2\" Threaded Fast Fill.\u003c\/p\u003e\u003cp\u003eThis boiler feed valve reduces incoming water pressure and automatically maintains fill pressure in a closed hydronic heating system. The fast fill feature allows quick filling and purging of the system during startup and service.\u003c\/p\u003e\u003cp\u003eConfirm the 1\/2\" connection style before installation. Install it in the cold water make-up line with a backflow preventer where local code requires one, and set the fill pressure to suit the height of the system.\u003c\/p\u003e\u003ch3\u003eSpecifications\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Taco Comfort Solutions\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part #:\u003c\/strong\u003e 329-T3\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSize:\u003c\/strong\u003e 1\/2\"\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eConnection:\u003c\/strong\u003e Threaded\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 687752022261\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCategory:\u003c\/strong\u003e System Fill Tanks \u0026amp; Autofills\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eSee also: \u003ca href=\"\/collections\/system-fill-tanks-autofills\"\u003eSystem Fill Tanks \u0026amp; Autofills\u003c\/a\u003e, \u003ca href=\"\/collections\/expansion-tanks-heating\"\u003eHeating Expansion Tanks\u003c\/a\u003e, \u003ca href=\"\/collections\/taco-comfort-solutions\"\u003eTaco Comfort Solutions\u003c\/a\u003e, \u003ca href=\"\/collections\/heating\"\u003eHeating\u003c\/a\u003e\u003c\/p\u003e","brand":"Taco Comfort Solutions","offers":[{"title":"Default Title","offer_id":44353379762279,"sku":"TACO-329-T3","price":131.32,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0651\/2253\/3479\/files\/Taco_329-2_bd49f4e3-da91-422c-b476-2d85aec0d326.png?v=1785831908"},{"product_id":"resideo-fm911-u-1-2-in-boiler-fill-valve-and-backflow-preventer-combo-assembly","title":"Resideo FM911\/U 1\/2 in Boiler Fill Valve and Backflow Preventer Combo Assembly","description":"\u003cp\u003e1\/2 in boiler fill valve and backflow preventer combination assembly, supplied with both union sweat and union threaded tailpieces.\u003c\/p\u003e\u003ch3\u003eSpecifications\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Resideo (Honeywell Home)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part #:\u003c\/strong\u003e FM911\/U\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eApplication:\u003c\/strong\u003e Boiler Feed Water Control\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePipe Size:\u003c\/strong\u003e 1 in\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDN Size:\u003c\/strong\u003e DN15\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIncludes:\u003c\/strong\u003e Union nut, Tailpiece with Sweat and NPT connections\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCompatible With:\u003c\/strong\u003e Hot Water\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWarranty:\u003c\/strong\u003e 1 Year\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eValve Body Material:\u003c\/strong\u003e Brass\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eColor:\u003c\/strong\u003e Black, Brass, Red\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProduct Weight:\u003c\/strong\u003e 1.8 kg, 4 lb\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 085267260350\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCountry of Origin:\u003c\/strong\u003e IT\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCategory:\u003c\/strong\u003e System Fill Tanks \u0026amp; Autofills\u003c\/li\u003e\n\u003c\/ul\u003e\u003cdiv class=\"ths-mfr-data\"\u003e\n\u003ch3\u003eFull Specifications\u003c\/h3\u003e\n\u003ctable class=\"ths-spec-table\"\u003e\u003ctbody\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eApplication\u003c\/th\u003e\n\u003ctd\u003eBoiler Feed Water Control\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003ePipe Size\u003c\/th\u003e\n\u003ctd\u003e1 in\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eDN Size\u003c\/th\u003e\n\u003ctd\u003eDN15\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eIncludes\u003c\/th\u003e\n\u003ctd\u003eUnion nut, Tailpiece with Sweat and NPT connections\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eCompatible With\u003c\/th\u003e\n\u003ctd\u003eHot Water\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eWarranty\u003c\/th\u003e\n\u003ctd\u003e1 Year\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eValve Body Material\u003c\/th\u003e\n\u003ctd\u003eBrass\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eColor\u003c\/th\u003e\n\u003ctd\u003eBlack, Brass, Red\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eProduct Weight\u003c\/th\u003e\n\u003ctd\u003e1.8 kg, 4 lb\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\u003c\/table\u003e\n\u003ch3\u003eDocuments \u0026amp; Downloads\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/digitalassets.resideo.com\/damroot\/Original\/10014\/33-00022.pdf\" target=\"_blank\" rel=\"noopener\"\u003eInstallation Instructions for VF06-100-SUSUT, FM911 Dialset Boiler Fill Valve (English)\u003c\/a\u003e (0.5MB PDF)\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/digitalassets.resideo.com\/damroot\/Original\/10015\/63-9296.pdf\" target=\"_blank\" rel=\"noopener\"\u003eTK Series Combination Boiler Trim Kit Sell Sheet (English)\u003c\/a\u003e (0.9MB PDF)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e","brand":"Resideo","offers":[{"title":"Default Title","offer_id":50331157823591,"sku":"HONE-FM911\/U","price":152.2,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0651\/2253\/3479\/files\/FM911-c3-6.jpg?v=1790429693"},{"product_id":"caleffi-north-america-535056a-autofilltm-3-4-union-press-with-pressure-gauge","title":"Caleffi North America 535056A AutoFill™ 3\/4\" Union Press with Pressure Gauge","description":"\u003cp\u003eCaleffi North America 535056A is an AutoFill™ assembly with 3\/4 in. union press connections and a pressure gauge.\u003c\/p\u003e\u003cp\u003eAutoFill valves are used to fill a hydronic heating system and keep its pressure up, and the included gauge lets you read system pressure at the fill point.\u003c\/p\u003e\u003cp\u003eThe connections are press, so you need a compatible press tool and tubing. Confirm the 3\/4 in. size against your piping, and review the data sheet, installation manual and submittal below before ordering.\u003c\/p\u003e\u003ch3\u003eSpecifications\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Caleffi North America\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part #:\u003c\/strong\u003e 535056A\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eConnection Type:\u003c\/strong\u003e Press\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSize:\u003c\/strong\u003e 3\/4\"\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eType:\u003c\/strong\u003e AutoFill\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 8016615471212\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCategory:\u003c\/strong\u003e System Fill Tanks \u0026amp; Autofills\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eDocuments\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/res.cloudinary.com\/dzhpkjoqj\/Caleffi\/535056A_CALE-535056A_8016615471212_TechB.pdf\" target=\"_blank\" rel=\"noopener\"\u003eTechnical Data Sheet\u003c\/a\u003e (PDF)\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/res.cloudinary.com\/dzhpkjoqj\/Caleffi\/535056A_CALE-535056A_8016615471212_Inst.pdf\" target=\"_blank\" rel=\"noopener\"\u003eInstallation and Operation Manual\u003c\/a\u003e (PDF)\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/res.cloudinary.com\/dzhpkjoqj\/Caleffi\/535056A_CALE-535056A_8016615471212_Sub.pdf\" target=\"_blank\" rel=\"noopener\"\u003eSubmittal Sheet\u003c\/a\u003e (PDF)\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eSee also: \u003ca href=\"\/collections\/system-fill-tanks-autofills\"\u003esystem fill tanks and autofills\u003c\/a\u003e, \u003ca href=\"\/collections\/caleffi-north-america\"\u003eall Caleffi North America products\u003c\/a\u003e.\u003c\/p\u003e","brand":"Caleffi","offers":[{"title":"Default Title","offer_id":50357525250151,"sku":"CALE-535056A","price":163.34,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0651\/2253\/3479\/files\/535056A_CALE-535056A_8016615471212.jpg?v=1790828984"},{"product_id":"caleffi-north-america-574161a-1-fnpt-x-1-npt-male-union","title":"Caleffi 574161A AutoFill 1\" FNPT x 1\" NPT Male Union Fill Valve with Testable Backflow Preventer","description":"\u003cp\u003eCaleffi North America 574161A is a 1 in. FNPT x 1 in. NPT male union that the supplier lists under Caleffi backflow preventer products.\u003c\/p\u003e\u003cp\u003eBackflow preventers protect the potable water supply from contamination, and local code usually sets the type of device, its installation position and its required testing.\u003c\/p\u003e\u003cp\u003eThe supplier listing gives few details for this part, so review the technical data, installation and operation manual and submittal linked below to confirm the exact part and its connections before ordering.\u003c\/p\u003e\u003ch3\u003eSpecifications\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Caleffi North America\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part #:\u003c\/strong\u003e 574161A\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eConnection Type:\u003c\/strong\u003e FIP\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSize:\u003c\/strong\u003e 1\"\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 8016615669404\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCategory:\u003c\/strong\u003e Backflow Preventers\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eDocuments\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/res.cloudinary.com\/dzhpkjoqj\/Caleffi\/574161A_CALE-574161A_8016615669404_TechB.pdf\" target=\"_blank\" rel=\"noopener\"\u003eTechnical Data Sheet\u003c\/a\u003e (PDF)\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/res.cloudinary.com\/dzhpkjoqj\/Caleffi\/574161A_CALE-574161A_8016615669404_Inst.pdf\" target=\"_blank\" rel=\"noopener\"\u003eInstallation and Operation Manual\u003c\/a\u003e (PDF)\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/res.cloudinary.com\/dzhpkjoqj\/Caleffi\/574161A_CALE-574161A_8016615669404_Sub.pdf\" target=\"_blank\" rel=\"noopener\"\u003eSubmittal Sheet\u003c\/a\u003e (PDF)\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eSee also: \u003ca href=\"\/collections\/caleffi-north-america\"\u003eall Caleffi North America products\u003c\/a\u003e.\u003c\/p\u003e","brand":"Caleffi","offers":[{"title":"Default Title","offer_id":50357525807207,"sku":"CALE-574161A","price":588.35,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0651\/2253\/3479\/files\/574161A_CALE-574161A_8016615669404.jpg?v=1790828988"},{"product_id":"taco-comfort-solutions-335u-075-t1-boiler-feed-valve-brass-3-4-npt-x-3-4-union-npt","title":"Taco Comfort Solutions 335U-075-T1 Boiler Feed Valve, Brass, 3\/4\" NPT x 3\/4\" Union NPT","description":"\u003cp\u003eTaco Comfort Solutions 335U-075-T1 is a brass boiler feed valve with 3\/4\" NPT x 3\/4\" union NPT connections.\u003c\/p\u003e\u003cp\u003eThe manufacturer says it automatically feeds water to a system whenever the pressure drops below the valve pressure setting. The dual control combines the boiler feed valve with an in-line pressure relief valve connected at the outlet end.\u003c\/p\u003e\u003cp\u003eThe backflow feature helps prevent contamination of the potable water system if supply pressure should fail. Check the connection sizes and your system pressure requirements before ordering.\u003c\/p\u003e\u003ch3\u003eSpecifications\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Taco Comfort Solutions\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part #:\u003c\/strong\u003e 335U-075-T1\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eConnection Size:\u003c\/strong\u003e 3\/4\"\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eConnection Type:\u003c\/strong\u003e NPT\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial:\u003c\/strong\u003e Brass\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCategory:\u003c\/strong\u003e System Fill Tanks \u0026amp; Autofills\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eSee also: \u003ca href=\"\/collections\/system-fill-tanks-autofills\"\u003esystem fill tanks and autofills\u003c\/a\u003e, \u003ca href=\"\/collections\/taco-comfort-solutions\"\u003eall Taco Comfort Solutions products\u003c\/a\u003e.\u003c\/p\u003e","brand":"Taco Comfort Solutions","offers":[{"title":"Default Title","offer_id":50357604778087,"sku":"TACO-335U-075-T1","price":165.81,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0651\/2253\/3479\/files\/Taco_335.jpg?v=1790829578"},{"product_id":"caleffi-573016a-573-combo-autofill-backflow-preventer-fill-valve-1-2-press-x-press-with-pressure-gauge-asse-1012","title":"Caleffi 573016A 573 COMBO AutoFill Backflow Preventer \u0026 Fill Valve 1\/2\" Press x Press with Pressure Gauge, ASSE 1012","description":"\u003cp\u003eThe Caleffi 573016A COMBO AutoFill combines an ASSE 1012 backflow preventer and an automatic fill (pressure reducing) valve in one 1\/2\" body with a pressure gauge, with press x press connections. It fills and maintains pressure in a closed hydronic heating system.\u003c\/p\u003e\u003cp\u003eInstalled on the cold water make-up line to a boiler, the fill valve keeps the system at its set fill pressure while the dual check backflow section with atmospheric vent protects the potable supply. Combining both functions in one compact unit saves space and connections compared with separate devices.\u003c\/p\u003e\u003cp\u003eBefore ordering, confirm the 1\/2\" press x press connections and your required fill pressure; check the installation manual for the adjustment range. Allow for drainage from the backflow vent port.\u003c\/p\u003e\u003ch3\u003eSpecifications\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Caleffi\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part #:\u003c\/strong\u003e 573016A\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSeries:\u003c\/strong\u003e 573 COMBO AutoFill\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eType:\u003c\/strong\u003e Backflow Preventer and Automatic Fill Valve Combination\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSize:\u003c\/strong\u003e 1\/2\"\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eConnection:\u003c\/strong\u003e press x press\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMax Temperature:\u003c\/strong\u003e 150F\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMax Pressure:\u003c\/strong\u003e 150 psi\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial:\u003c\/strong\u003e Brass\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIncludes:\u003c\/strong\u003e Pressure Gauge\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStandards:\u003c\/strong\u003e ASSE 1012\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 8016615576603\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCategory:\u003c\/strong\u003e System Fill Tanks \u0026amp; Autofills\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eDocuments\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/res.cloudinary.com\/dzhpkjoqj\/Caleffi\/573016A_CALE-573016A_8016615576603_TechB.pdf\" target=\"_blank\" rel=\"noopener\"\u003eTechnical Data Sheet\u003c\/a\u003e (PDF)\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/res.cloudinary.com\/dzhpkjoqj\/Caleffi\/573016A_CALE-573016A_8016615576603_Inst.pdf\" target=\"_blank\" rel=\"noopener\"\u003eInstallation \u0026amp; Operation Manual\u003c\/a\u003e (PDF)\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/res.cloudinary.com\/dzhpkjoqj\/Caleffi\/573016A_CALE-573016A_8016615576603_Sub.pdf\" target=\"_blank\" rel=\"noopener\"\u003eSubmittal Sheet\u003c\/a\u003e (PDF)\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/res.cloudinary.com\/dzhpkjoqj\/Caleffi\/573016A_CALE-573016A_8016615576603_Sell.pdf\" target=\"_blank\" rel=\"noopener\"\u003eProduct Brochure\u003c\/a\u003e (PDF)\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eSee also: \u003ca href=\"\/collections\/system-fill-tanks-autofills\"\u003esystem fill tanks \u0026amp; autofills\u003c\/a\u003e, \u003ca href=\"\/collections\/caleffi-north-america\"\u003eall Caleffi products\u003c\/a\u003e.\u003c\/p\u003e","brand":"Caleffi","offers":[{"title":"Default Title","offer_id":50517447311463,"sku":"CALE-573016A","price":262.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0651\/2253\/3479\/files\/573016A_CALE-573016A_8016615576603.jpg?v=1792424436"},{"product_id":"caleffi-573002a-573-combo-autofill-backflow-preventer-fill-valve-1-2-npt-x-npt-asse-1012","title":"Caleffi 573002A 573 COMBO AutoFill Backflow Preventer \u0026 Fill Valve 1\/2\" NPT x NPT, ASSE 1012","description":"\u003cp\u003eThe Caleffi 573002A COMBO AutoFill combines an ASSE 1012 backflow preventer and an automatic fill (pressure reducing) valve in one 1\/2\" body, with NPT x NPT threaded connections. It fills and maintains pressure in a closed hydronic heating system.\u003c\/p\u003e\u003cp\u003eInstalled on the cold water make-up line to a boiler, the fill valve keeps the system at its set fill pressure while the dual check backflow section with atmospheric vent protects the potable supply. Combining both functions in one compact unit saves space and connections compared with separate devices.\u003c\/p\u003e\u003cp\u003eBefore ordering, confirm the 1\/2\" NPT x NPT threaded connections and your required fill pressure; check the installation manual for the adjustment range. Allow for drainage from the backflow vent port.\u003c\/p\u003e\u003ch3\u003eSpecifications\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Caleffi\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part #:\u003c\/strong\u003e 573002A\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSeries:\u003c\/strong\u003e 573 COMBO AutoFill\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eType:\u003c\/strong\u003e Backflow Preventer and Automatic Fill Valve Combination\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSize:\u003c\/strong\u003e 1\/2\"\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eConnection:\u003c\/strong\u003e NPT x NPT threaded\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMax Temperature:\u003c\/strong\u003e 150F\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMax Pressure:\u003c\/strong\u003e 175 psi\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial:\u003c\/strong\u003e Brass\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStandards:\u003c\/strong\u003e ASSE 1012\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 8016615962000\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCategory:\u003c\/strong\u003e System Fill Tanks \u0026amp; Autofills\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eDocuments\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/res.cloudinary.com\/dzhpkjoqj\/Caleffi\/573002A_CALE-573002A_8016615962000_TechB.pdf\" target=\"_blank\" rel=\"noopener\"\u003eTechnical Data Sheet\u003c\/a\u003e (PDF)\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/res.cloudinary.com\/dzhpkjoqj\/Caleffi\/573002A_CALE-573002A_8016615962000_Inst.pdf\" target=\"_blank\" rel=\"noopener\"\u003eInstallation \u0026amp; Operation Manual\u003c\/a\u003e (PDF)\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/res.cloudinary.com\/dzhpkjoqj\/Caleffi\/573002A_CALE-573002A_8016615962000_Sub.pdf\" target=\"_blank\" rel=\"noopener\"\u003eSubmittal Sheet\u003c\/a\u003e (PDF)\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/res.cloudinary.com\/dzhpkjoqj\/Caleffi\/573002A_CALE-573002A_8016615962000_Sell.pdf\" target=\"_blank\" rel=\"noopener\"\u003eProduct Brochure\u003c\/a\u003e (PDF)\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eSee also: \u003ca href=\"\/collections\/system-fill-tanks-autofills\"\u003esystem fill tanks \u0026amp; autofills\u003c\/a\u003e, \u003ca href=\"\/collections\/caleffi-north-america\"\u003eall Caleffi products\u003c\/a\u003e.\u003c\/p\u003e","brand":"Caleffi","offers":[{"title":"Default Title","offer_id":50517448622183,"sku":"CALE-573002A","price":217.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0651\/2253\/3479\/files\/573002A_CALE-573002A_8016615962000.jpg?v=1792424483"},{"product_id":"caleffi-573017a-573-combo-autofill-backflow-preventer-fill-valve-1-2-press-inlet-x-npt-outlet-with-pressure-gauge-asse-1012","title":"Caleffi 573017A 573 COMBO AutoFill Backflow Preventer \u0026 Fill Valve 1\/2\" Press Inlet x NPT Outlet with Pressure Gauge, ASSE 1012","description":"\u003cp\u003eThe Caleffi 573017A COMBO AutoFill combines an ASSE 1012 backflow preventer and an automatic fill (pressure reducing) valve in one 1\/2\" body with a pressure gauge, with press inlet x NPT outlet connections. It fills and maintains pressure in a closed hydronic heating system.\u003c\/p\u003e\u003cp\u003eInstalled on the cold water make-up line to a boiler, the fill valve keeps the system at its set fill pressure while the dual check backflow section with atmospheric vent protects the potable supply. Combining both functions in one compact unit saves space and connections compared with separate devices.\u003c\/p\u003e\u003cp\u003eBefore ordering, confirm the 1\/2\" press inlet x NPT outlet connections and your required fill pressure; check the installation manual for the adjustment range. Allow for drainage from the backflow vent port.\u003c\/p\u003e\u003ch3\u003eSpecifications\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Caleffi\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part #:\u003c\/strong\u003e 573017A\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSeries:\u003c\/strong\u003e 573 COMBO AutoFill\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eType:\u003c\/strong\u003e Backflow Preventer and Automatic Fill Valve Combination\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSize:\u003c\/strong\u003e 1\/2\"\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eConnection:\u003c\/strong\u003e press inlet x NPT outlet\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMax Temperature:\u003c\/strong\u003e 150F\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMax Pressure:\u003c\/strong\u003e 175 psi\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial:\u003c\/strong\u003e Brass\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIncludes:\u003c\/strong\u003e Pressure Gauge\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStandards:\u003c\/strong\u003e ASSE 1012\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 8016615576610\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCategory:\u003c\/strong\u003e System Fill Tanks \u0026amp; Autofills\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eDocuments\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/res.cloudinary.com\/dzhpkjoqj\/Caleffi\/573017A_CALE-573017A_8016615576610_TechB.pdf\" target=\"_blank\" rel=\"noopener\"\u003eTechnical Data Sheet\u003c\/a\u003e (PDF)\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/res.cloudinary.com\/dzhpkjoqj\/Caleffi\/573017A_CALE-573017A_8016615576610_Inst.pdf\" target=\"_blank\" rel=\"noopener\"\u003eInstallation \u0026amp; Operation Manual\u003c\/a\u003e (PDF)\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/res.cloudinary.com\/dzhpkjoqj\/Caleffi\/573017A_CALE-573017A_8016615576610_Sub.pdf\" target=\"_blank\" rel=\"noopener\"\u003eSubmittal Sheet\u003c\/a\u003e (PDF)\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/res.cloudinary.com\/dzhpkjoqj\/Caleffi\/573017A_CALE-573017A_8016615576610_Sell.pdf\" target=\"_blank\" rel=\"noopener\"\u003eProduct Brochure\u003c\/a\u003e (PDF)\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eSee also: \u003ca href=\"\/collections\/system-fill-tanks-autofills\"\u003esystem fill tanks \u0026amp; autofills\u003c\/a\u003e, \u003ca href=\"\/collections\/caleffi-north-america\"\u003eall Caleffi products\u003c\/a\u003e.\u003c\/p\u003e","brand":"Caleffi","offers":[{"title":"Default Title","offer_id":50517450752103,"sku":"CALE-573017A","price":249.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0651\/2253\/3479\/files\/573017A_CALE-573017A_8016615576610.jpg?v=1792424560"},{"product_id":"caleffi-573012a-573-combo-autofill-backflow-preventer-fill-valve-1-2-npt-x-npt-with-pressure-gauge-asse-1012","title":"Caleffi 573012A 573 COMBO AutoFill Backflow Preventer \u0026 Fill Valve 1\/2\" NPT x NPT with Pressure Gauge, ASSE 1012","description":"\u003cp\u003eThe Caleffi 573012A COMBO AutoFill combines an ASSE 1012 backflow preventer and an automatic fill (pressure reducing) valve in one 1\/2\" body with a pressure gauge, with NPT x NPT threaded connections. It fills and maintains pressure in a closed hydronic heating system.\u003c\/p\u003e\u003cp\u003eInstalled on the cold water make-up line to a boiler, the fill valve keeps the system at its set fill pressure while the dual check backflow section with atmospheric vent protects the potable supply. Combining both functions in one compact unit saves space and connections compared with separate devices.\u003c\/p\u003e\u003cp\u003eBefore ordering, confirm the 1\/2\" NPT x NPT threaded connections and your required fill pressure; check the installation manual for the adjustment range. Allow for drainage from the backflow vent port.\u003c\/p\u003e\u003ch3\u003eSpecifications\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Caleffi\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part #:\u003c\/strong\u003e 573012A\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSeries:\u003c\/strong\u003e 573 COMBO AutoFill\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eType:\u003c\/strong\u003e Backflow Preventer and Automatic Fill Valve Combination\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSize:\u003c\/strong\u003e 1\/2\"\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eConnection:\u003c\/strong\u003e NPT x NPT threaded\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMax Temperature:\u003c\/strong\u003e 150F\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMax Pressure:\u003c\/strong\u003e 175 psi\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial:\u003c\/strong\u003e Brass\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIncludes:\u003c\/strong\u003e Pressure Gauge\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStandards:\u003c\/strong\u003e ASSE 1012\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 8016615504958\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCategory:\u003c\/strong\u003e System Fill Tanks \u0026amp; Autofills\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eDocuments\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/res.cloudinary.com\/dzhpkjoqj\/Caleffi\/573012A_CALE-573012A_8016615504958_TechB.pdf\" target=\"_blank\" rel=\"noopener\"\u003eTechnical Data Sheet\u003c\/a\u003e (PDF)\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/res.cloudinary.com\/dzhpkjoqj\/Caleffi\/573012A_CALE-573012A_8016615504958_Inst.pdf\" target=\"_blank\" rel=\"noopener\"\u003eInstallation \u0026amp; Operation Manual\u003c\/a\u003e (PDF)\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/res.cloudinary.com\/dzhpkjoqj\/Caleffi\/573012A_CALE-573012A_8016615504958_Sub.pdf\" target=\"_blank\" rel=\"noopener\"\u003eSubmittal Sheet\u003c\/a\u003e (PDF)\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/res.cloudinary.com\/dzhpkjoqj\/Caleffi\/573012A_CALE-573012A_8016615504958_Sell.pdf\" target=\"_blank\" rel=\"noopener\"\u003eProduct Brochure\u003c\/a\u003e (PDF)\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eSee also: \u003ca href=\"\/collections\/system-fill-tanks-autofills\"\u003esystem fill tanks \u0026amp; autofills\u003c\/a\u003e, \u003ca href=\"\/collections\/caleffi-north-america\"\u003eall Caleffi products\u003c\/a\u003e.\u003c\/p\u003e","brand":"Caleffi","offers":[{"title":"Default Title","offer_id":50517451112551,"sku":"CALE-573012A","price":235.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0651\/2253\/3479\/files\/573012A_CALE-573012A_8016615504958.jpg?v=1792424575"},{"product_id":"caleffi-574151a-574-combo-autofill-rpz-backflow-preventer-fill-valve-3-4-npt-with-pressure-gauge-asse-1013-low-lead","title":"Caleffi 574151A 574 COMBO AutoFill RPZ Backflow Preventer \u0026 Fill Valve 3\/4\" NPT with Pressure Gauge, ASSE 1013, Low Lead","description":"\u003cp\u003eThe Caleffi 574151A COMBO AutoFill combines an ASSE 1013 reduced pressure zone (RPZ) backflow preventer and an automatic fill valve in one 3\/4\" NPT low lead brass body with a pressure gauge. It fills and maintains pressure in closed hydronic systems where a higher level of backflow protection is required.\u003c\/p\u003e\u003cp\u003eRPZ protection is typically required where the heating system water is treated with chemicals such as glycol antifreeze or corrosion inhibitors. Combining the RPZ and the fill valve in one unit reduces the space and the number of connections on the boiler make-up line.\u003c\/p\u003e\u003cp\u003eBefore ordering, confirm the 3\/4\" NPT connections and your local code requirements for RPZ devices, including testing and the need for a drain at the relief port. Check the installation manual for the fill pressure adjustment range.\u003c\/p\u003e\u003ch3\u003eSpecifications\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Caleffi\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part #:\u003c\/strong\u003e 574151A\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSeries:\u003c\/strong\u003e 574 COMBO AutoFill\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eType:\u003c\/strong\u003e RPZ Backflow Preventer and Automatic Fill Valve Combination\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSize:\u003c\/strong\u003e 3\/4\"\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eConnection:\u003c\/strong\u003e 3\/4\" NPT threaded\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMax Temperature:\u003c\/strong\u003e 140F\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMax Pressure:\u003c\/strong\u003e 140 psi\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial:\u003c\/strong\u003e Low lead brass\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIncludes:\u003c\/strong\u003e Pressure Gauge\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStandards:\u003c\/strong\u003e ASSE 1013\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 8016615576399\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCategory:\u003c\/strong\u003e System Fill Tanks \u0026amp; Autofills\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eDocuments\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/res.cloudinary.com\/dzhpkjoqj\/Caleffi\/574151A_CALE-574151A_8016615576399_TechB.pdf\" target=\"_blank\" rel=\"noopener\"\u003eTechnical Data Sheet\u003c\/a\u003e (PDF)\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/res.cloudinary.com\/dzhpkjoqj\/Caleffi\/574151A_CALE-574151A_8016615576399_Inst.pdf\" target=\"_blank\" rel=\"noopener\"\u003eInstallation \u0026amp; Operation Manual\u003c\/a\u003e (PDF)\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/res.cloudinary.com\/dzhpkjoqj\/Caleffi\/574151A_CALE-574151A_8016615576399_Sub.pdf\" target=\"_blank\" rel=\"noopener\"\u003eSubmittal Sheet\u003c\/a\u003e (PDF)\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eSee also: \u003ca href=\"\/collections\/system-fill-tanks-autofills\"\u003esystem fill tanks \u0026amp; autofills\u003c\/a\u003e, \u003ca href=\"\/collections\/caleffi-north-america\"\u003eall Caleffi products\u003c\/a\u003e.\u003c\/p\u003e","brand":"Caleffi","offers":[{"title":"Default Title","offer_id":50517452357735,"sku":"CALE-574151A","price":587.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0651\/2253\/3479\/files\/574151A_CALE-574151A_8016615576399.jpg?v=1792424626"},{"product_id":"caleffi-573019a-573-combo-autofill-backflow-preventer-fill-valve-1-2-sweat-inlet-x-npt-outlet-with-pressure-gauge-asse-1012","title":"Caleffi 573019A 573 COMBO AutoFill Backflow Preventer \u0026 Fill Valve 1\/2\" Sweat Inlet x NPT Outlet with Pressure Gauge, ASSE 1012","description":"\u003cp\u003eThe Caleffi 573019A COMBO AutoFill combines an ASSE 1012 backflow preventer and an automatic fill (pressure reducing) valve in one 1\/2\" body with a pressure gauge, with sweat inlet x NPT outlet connections. It fills and maintains pressure in a closed hydronic heating system.\u003c\/p\u003e\u003cp\u003eInstalled on the cold water make-up line to a boiler, the fill valve keeps the system at its set fill pressure while the dual check backflow section with atmospheric vent protects the potable supply. Combining both functions in one compact unit saves space and connections compared with separate devices.\u003c\/p\u003e\u003cp\u003eBefore ordering, confirm the 1\/2\" sweat inlet x NPT outlet connections and your required fill pressure; check the installation manual for the adjustment range. Allow for drainage from the backflow vent port.\u003c\/p\u003e\u003ch3\u003eSpecifications\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Caleffi\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part #:\u003c\/strong\u003e 573019A\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSeries:\u003c\/strong\u003e 573 COMBO AutoFill\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eType:\u003c\/strong\u003e Backflow Preventer and Automatic Fill Valve Combination\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSize:\u003c\/strong\u003e 1\/2\"\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eConnection:\u003c\/strong\u003e sweat inlet x NPT outlet\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMax Temperature:\u003c\/strong\u003e 150F\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMax Pressure:\u003c\/strong\u003e 175 psi\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial:\u003c\/strong\u003e Brass\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIncludes:\u003c\/strong\u003e Pressure Gauge\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStandards:\u003c\/strong\u003e ASSE 1012\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 8016615504965\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCategory:\u003c\/strong\u003e System Fill Tanks \u0026amp; Autofills\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eDocuments\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/res.cloudinary.com\/dzhpkjoqj\/Caleffi\/573019A_CALE-573019A_8016615504965_TechB.pdf\" target=\"_blank\" rel=\"noopener\"\u003eTechnical Data Sheet\u003c\/a\u003e (PDF)\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/res.cloudinary.com\/dzhpkjoqj\/Caleffi\/573019A_CALE-573019A_8016615504965_Inst.pdf\" target=\"_blank\" rel=\"noopener\"\u003eInstallation \u0026amp; Operation Manual\u003c\/a\u003e (PDF)\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/res.cloudinary.com\/dzhpkjoqj\/Caleffi\/573019A_CALE-573019A_8016615504965_Sub.pdf\" target=\"_blank\" rel=\"noopener\"\u003eSubmittal Sheet\u003c\/a\u003e (PDF)\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/res.cloudinary.com\/dzhpkjoqj\/Caleffi\/573019A_CALE-573019A_8016615504965_Sell.pdf\" target=\"_blank\" rel=\"noopener\"\u003eProduct Brochure\u003c\/a\u003e (PDF)\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eSee also: \u003ca href=\"\/collections\/system-fill-tanks-autofills\"\u003esystem fill tanks \u0026amp; autofills\u003c\/a\u003e, \u003ca href=\"\/collections\/caleffi-north-america\"\u003eall Caleffi products\u003c\/a\u003e.\u003c\/p\u003e","brand":"Caleffi","offers":[{"title":"Default Title","offer_id":50517455306855,"sku":"CALE-573019A","price":225.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0651\/2253\/3479\/files\/573019A_CALE-573019A_8016615504965.jpg?v=1792424717"}],"url":"https:\/\/www.thehousesupplier.com\/collections\/boiler-fill-valves.oembed","provider":"The House Supplier","version":"1.0","type":"link"}