{"product_id":"backstop-12-twh2-thermal-expansion-tank-2-gallon","title":"Backstop 12-TWH2 Thermal Expansion Tank 2 Gallon","description":"\u003ch3\u003eProduct Description\u003c\/h3\u003e\u003cp\u003eThe BACKSTOP 12-TWH2 is a 2-gallon thermal expansion tank designed to absorb the increased water volume that results from thermal expansion in closed domestic hot water systems. When a water heater heats cold water, the water expands. In a closed plumbing system, that expanded volume must go somewhere  -  this tank provides the necessary buffer to protect system pressure. The 2-gallon capacity suits residential water heater installations where local codes require thermal expansion control. Licensed plumbers and mechanical contractors install this tank as a code-compliance component in closed-loop domestic water systems.\u003c\/p\u003e\u003cp\u003eThe 12-TWH2 is applied in residential and light commercial plumbing systems served by a storage-type water heater. It is particularly relevant where a backflow preventer, pressure-reducing valve, or check valve creates a closed system condition. The tank connects to the cold-water supply line near the water heater and works passively to maintain safe system pressure without requiring electrical power or operator input.\u003c\/p\u003e\u003ch4\u003eKey Features\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e2-gallon tank capacity sized for residential closed water heater systems\u003c\/li\u003e\n\u003cli\u003ePassive operation  -  no electrical connections required\u003c\/li\u003e\n\u003cli\u003eDesigned for closed domestic hot water plumbing systems\u003c\/li\u003e\n\u003cli\u003eSold as a single unit\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eCompatibility\u003c\/h4\u003e\u003cp\u003eDesigned as an OEM-style replacement or new-installation thermal expansion tank for residential closed domestic hot water plumbing systems.\u003c\/p\u003e\u003ch4\u003eInstallation Notes\u003c\/h4\u003e\u003cp\u003eInstallation is performed by a licensed plumber in accordance with the International Plumbing Code (IPC) and applicable local amendments. Shut off the cold-water supply and depressurize the system before connecting the tank. The tank should be installed on the cold-water supply line serving the water heater, upstream of the heater connection. Verify the pre-charge air pressure in the tank matches the system supply pressure before completing the installation.\u003c\/p\u003e\u003ch4\u003eTechnical Specifications\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eTank Capacity\u003c\/strong\u003e: 2 gallons\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProduct Type\u003c\/strong\u003e: Thermal Expansion Tank\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSelling Unit\u003c\/strong\u003e: Single\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eStandard Information\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand\u003c\/strong\u003e: BACKSTOP\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part Number\u003c\/strong\u003e: 12-TWH2\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"BACKSTOP","offers":[{"title":"Default Title","offer_id":68058568098098,"sku":"12-TWH2","price":76.77,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0270\/4519\/9983\/files\/b41947af78bcad937324fee7e919cc9f.png?v=1793019373","url":"https:\/\/voomisupply.com\/products\/backstop-12-twh2-thermal-expansion-tank-2-gallon","provider":"Voomi Supply","version":"1.0","type":"link"}