{"product_id":"caleffi-3-bar-safety-valve-1-2-o-ring-push-fit-a312438-cst","title":"Caleffi 3 Bar Safety Valve 1\/2\" O-Ring Push Fit | A312438 CST","description":"\u003c!-- SEO Product Name: Caleffi 3 Bar Safety Valve 1\/2\" O-Ring Push Fit | A312438 CST --\u003e\n\u003cdiv style=\"font-size:16px; max-width:900px; line-height:1.6; color:#222222;\"\u003e\n\u003cp\u003eThe \u003cstrong\u003eCaleffi A312438 CST\u003c\/strong\u003e is a \u003cstrong\u003e3 bar safety relief valve\u003c\/strong\u003e from the Caleffi \u003cstrong\u003e312 series\u003c\/strong\u003e, supplied with a \u003cstrong\u003e1\/2 inch O-ring push-fit connection\u003c\/strong\u003e and a \u003cstrong\u003e1\/2 inch BSP threaded connection\u003c\/strong\u003e. It protects \u003cstrong\u003ehot water cylinders\u003c\/strong\u003e in domestic hot water systems and \u003cstrong\u003eboilers and other heating components\u003c\/strong\u003e by opening and discharging to atmosphere before pressure reaches a dangerous level.\u003c\/p\u003e\n\u003cp\u003eBuilt with a \u003cstrong\u003ebrass body and cover\u003c\/strong\u003e, an \u003cstrong\u003eEPDM diaphragm\u003c\/strong\u003e and a \u003cstrong\u003estainless steel spring\u003c\/strong\u003e, it handles \u003cstrong\u003ewater and air\u003c\/strong\u003e from \u003cstrong\u003e5 to 110 °C\u003c\/strong\u003e with a \u003cstrong\u003emaximum static pressure of 10 bar\u003c\/strong\u003e. The valve is \u003cstrong\u003eWRAS approved\u003c\/strong\u003e, \u003cstrong\u003eCE marked\u003c\/strong\u003e and classified \u003cstrong\u003ePED category IV\u003c\/strong\u003e, making it a dependable like-for-like replacement for installers who need a certified 3 bar valve.\u003c\/p\u003e\n\u003cdiv style=\"display:flex; flex-wrap:wrap; gap:10px; margin:20px 0;\"\u003e\n\u003cdiv style=\"flex:1 1 130px; background:#008377CF; color:#ffffff; border-radius:8px; padding:14px 10px; text-align:center;\"\u003e\n\u003cdiv style=\"font-size:22px; font-weight:700;\"\u003e3 bar\u003c\/div\u003e\n\u003cdiv style=\"font-size:13px; margin-top:4px;\"\u003eSet pressure\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"flex:1 1 130px; background:#008377CF; color:#ffffff; border-radius:8px; padding:14px 10px; text-align:center;\"\u003e\n\u003cdiv style=\"font-size:22px; font-weight:700;\"\u003e5-110 °C\u003c\/div\u003e\n\u003cdiv style=\"font-size:13px; margin-top:4px;\"\u003eTemperature range\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"flex:1 1 130px; background:#008377CF; color:#ffffff; border-radius:8px; padding:14px 10px; text-align:center;\"\u003e\n\u003cdiv style=\"font-size:22px; font-weight:700;\"\u003e10 bar\u003c\/div\u003e\n\u003cdiv style=\"font-size:13px; margin-top:4px;\"\u003eMax static pressure\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"flex:1 1 130px; background:#008377CF; color:#ffffff; border-radius:8px; padding:14px 10px; text-align:center;\"\u003e\n\u003cdiv style=\"font-size:22px; font-weight:700;\"\u003e1\/2 in\u003c\/div\u003e\n\u003cdiv style=\"font-size:13px; margin-top:4px;\"\u003ePush-fit and BSP\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"flex:1 1 130px; background:#008377CF; color:#ffffff; border-radius:8px; padding:14px 10px; text-align:center;\"\u003e\n\u003cdiv style=\"font-size:22px; font-weight:700;\"\u003eWRAS\u003c\/div\u003e\n\u003cdiv style=\"font-size:13px; margin-top:4px;\"\u003eApproved product\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"flex:1 1 130px; background:#008377CF; color:#ffffff; border-radius:8px; padding:14px 10px; text-align:center;\"\u003e\n\u003cdiv style=\"font-size:22px; font-weight:700;\"\u003ePED IV\u003c\/div\u003e\n\u003cdiv style=\"font-size:13px; margin-top:4px;\"\u003eCE marked\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"border-left:5px solid #b42318; background:#fdecea; border-radius:6px; padding:12px 16px; margin:16px 0;\"\u003e\n\u003cdiv style=\"font-weight:700; color:#b42318; margin-bottom:4px;\"\u003eSafety and installation\u003c\/div\u003e\n\u003cdiv style=\"line-height:1.55; color:#222222;\"\u003eSafety relief valves are \u003cstrong\u003esafety-critical devices\u003c\/strong\u003e. On unvented hot water systems, installation must be by a \u003cstrong\u003eG3 qualified installer\u003c\/strong\u003e in line with Building Regulations Part G. The \u003cstrong\u003eoutlet must be piped to a safe, visible discharge point\u003c\/strong\u003e and never capped, plugged or restricted. Do not use the valve to control system pressure and do not fit it with any isolating valve between it and the protected system.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"border-left:5px solid #b54708; background:#fff4e5; border-radius:6px; padding:12px 16px; margin:16px 0;\"\u003e\n\u003cdiv style=\"font-weight:700; color:#b54708; margin-bottom:4px;\"\u003eCheck the connection type before ordering\u003c\/div\u003e\n\u003cdiv style=\"line-height:1.55; color:#222222;\"\u003eThis valve has a \u003cstrong\u003e1\/2 inch O-ring push-fit connection\u003c\/strong\u003e on one end and a \u003cstrong\u003e1\/2 inch BSP thread\u003c\/strong\u003e on the other. Manufacturer information for this part number describes the thread end as female, whereas some trade listings describe it as male. \u003cstrong\u003eCheck which thread you need against your fitting\u003c\/strong\u003e before ordering.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"border-left:5px solid #b54708; background:#fff4e5; border-radius:6px; padding:12px 16px; margin:16px 0;\"\u003e\n\u003cdiv style=\"font-weight:700; color:#b54708; margin-bottom:4px;\"\u003eMatch the set pressure to your system\u003c\/div\u003e\n\u003cdiv style=\"line-height:1.55; color:#222222;\"\u003eThe valve is factory set to \u003cstrong\u003e3 bar\u003c\/strong\u003e. The set pressure must be \u003cstrong\u003eat or below the lowest rated pressure of any component it protects\u003c\/strong\u003e, so confirm the maximum working pressure of your boiler, cylinder or heating components before fitting.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"border-left:5px solid #008377CF; background:#e6f4f2; border-radius:6px; padding:12px 16px; margin:16px 0;\"\u003e\n\u003cdiv style=\"font-weight:700; color:#008377CF; margin-bottom:4px;\"\u003eHow it works\u003c\/div\u003e\n\u003cdiv style=\"line-height:1.55; color:#222222;\"\u003eAs pressure rises to the \u003cstrong\u003e3.6 bar discharge pressure\u003c\/strong\u003e, the diaphragm valve opens and discharges to atmosphere. It then \u003cstrong\u003ere-seats at 2.4 bar\u003c\/strong\u003e, closing again once pressure has dropped back to a safe level.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"font-weight:700; font-size:18px; color:#008377CF; margin:24px 0 10px;\"\u003eKey features\u003c\/div\u003e\n\u003cdiv style=\"display:flex; flex-wrap:wrap; gap:12px;\"\u003e\n\u003cdiv style=\"flex:1 1 260px; border:1px solid #008377CF; border-top:4px solid #008377CF; border-radius:8px; padding:14px; background:#ffffff;\"\u003e\n\u003cdiv style=\"font-weight:700; color:#008377CF; margin-bottom:6px;\"\u003e3 bar set pressure\u003c\/div\u003e\n\u003cdiv style=\"font-size:15px; line-height:1.5; color:#333333;\"\u003eFactory set to \u003cstrong\u003e3 bar\u003c\/strong\u003e for typical domestic heating and hot water protection duties.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"flex:1 1 260px; border:1px solid #008377CF; border-top:4px solid #008377CF; border-radius:8px; padding:14px; background:#ffffff;\"\u003e\n\u003cdiv style=\"font-weight:700; color:#008377CF; margin-bottom:6px;\"\u003eCylinder and boiler protection\u003c\/div\u003e\n\u003cdiv style=\"font-size:15px; line-height:1.5; color:#333333;\"\u003eProtects \u003cstrong\u003ehot water storage cylinders\u003c\/strong\u003e and \u003cstrong\u003eboilers and other heating components\u003c\/strong\u003e from dangerous overpressure.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"flex:1 1 260px; border:1px solid #008377CF; border-top:4px solid #008377CF; border-radius:8px; padding:14px; background:#ffffff;\"\u003e\n\u003cdiv style=\"font-weight:700; color:#008377CF; margin-bottom:6px;\"\u003eO-ring push-fit connection\u003c\/div\u003e\n\u003cdiv style=\"font-size:15px; line-height:1.5; color:#333333;\"\u003eThe \u003cstrong\u003e1\/2 inch O-ring push-fit end\u003c\/strong\u003e allows quick, tool-light connection where a push-fit port is specified.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"flex:1 1 260px; border:1px solid #008377CF; border-top:4px solid #008377CF; border-radius:8px; padding:14px; background:#ffffff;\"\u003e\n\u003cdiv style=\"font-weight:700; color:#008377CF; margin-bottom:6px;\"\u003eBrass body, EPDM diaphragm\u003c\/div\u003e\n\u003cdiv style=\"font-size:15px; line-height:1.5; color:#333333;\"\u003e\n\u003cstrong\u003eBrass body and cover\u003c\/strong\u003e, \u003cstrong\u003eEPDM diaphragm\u003c\/strong\u003e, brass stem and \u003cstrong\u003estainless steel spring\u003c\/strong\u003e for long service life.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"flex:1 1 260px; border:1px solid #008377CF; border-top:4px solid #008377CF; border-radius:8px; padding:14px; background:#ffffff;\"\u003e\n\u003cdiv style=\"font-weight:700; color:#008377CF; margin-bottom:6px;\"\u003eWater and air\u003c\/div\u003e\n\u003cdiv style=\"font-size:15px; line-height:1.5; color:#333333;\"\u003eSuitable for \u003cstrong\u003ewater and air\u003c\/strong\u003e across a \u003cstrong\u003e5 to 110 °C\u003c\/strong\u003e temperature range.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"flex:1 1 260px; border:1px solid #008377CF; border-top:4px solid #008377CF; border-radius:8px; padding:14px; background:#ffffff;\"\u003e\n\u003cdiv style=\"font-weight:700; color:#008377CF; margin-bottom:6px;\"\u003eCertified product\u003c\/div\u003e\n\u003cdiv style=\"font-size:15px; line-height:1.5; color:#333333;\"\u003e\n\u003cstrong\u003eWRAS approved\u003c\/strong\u003e, \u003cstrong\u003eCE marked\u003c\/strong\u003e and classified \u003cstrong\u003ePED category IV\u003c\/strong\u003e.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"font-weight:700; font-size:18px; color:#008377CF; margin:24px 0 10px;\"\u003eTechnical specification\u003c\/div\u003e\n\u003cdiv style=\"border:1px solid #008377CF; border-radius:8px; overflow:hidden;\"\u003e\n\u003cdiv style=\"background:#008377CF; color:#ffffff; font-weight:700; padding:8px 14px;\"\u003eGeneral\u003c\/div\u003e\n\u003cdiv style=\"display:flex; flex-wrap:wrap; background:#f1f8f7; padding:8px 14px; border-bottom:1px solid #d9e8e6;\"\u003e\n\u003cdiv style=\"flex:1 1 220px; font-weight:600; color:#222222;\"\u003eBrand\u003c\/div\u003e\n\u003cdiv style=\"flex:2 1 300px; color:#333333;\"\u003eCaleffi\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"display:flex; flex-wrap:wrap; background:#ffffff; padding:8px 14px; border-bottom:1px solid #d9e8e6;\"\u003e\n\u003cdiv style=\"flex:1 1 220px; font-weight:600; color:#222222;\"\u003eManufacturer part number\u003c\/div\u003e\n\u003cdiv style=\"flex:2 1 300px; color:#333333;\"\u003eA312438 CST\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"display:flex; flex-wrap:wrap; background:#f1f8f7; padding:8px 14px; border-bottom:1px solid #d9e8e6;\"\u003e\n\u003cdiv style=\"flex:1 1 220px; font-weight:600; color:#222222;\"\u003eSeries\u003c\/div\u003e\n\u003cdiv style=\"flex:2 1 300px; color:#333333;\"\u003e312 safety relief valve\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"display:flex; flex-wrap:wrap; background:#ffffff; padding:8px 14px; border-bottom:1px solid #d9e8e6;\"\u003e\n\u003cdiv style=\"flex:1 1 220px; font-weight:600; color:#222222;\"\u003eValve type\u003c\/div\u003e\n\u003cdiv style=\"flex:2 1 300px; color:#333333;\"\u003eDiaphragm safety relief valve\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"display:flex; flex-wrap:wrap; background:#f1f8f7; padding:8px 14px; border-bottom:1px solid #d9e8e6;\"\u003e\n\u003cdiv style=\"flex:1 1 220px; font-weight:600; color:#222222;\"\u003eMedium\u003c\/div\u003e\n\u003cdiv style=\"flex:2 1 300px; color:#333333;\"\u003eWater and air\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"background:#008377CF; color:#ffffff; font-weight:700; padding:8px 14px;\"\u003eConnections\u003c\/div\u003e\n\u003cdiv style=\"display:flex; flex-wrap:wrap; background:#f1f8f7; padding:8px 14px; border-bottom:1px solid #d9e8e6;\"\u003e\n\u003cdiv style=\"flex:1 1 220px; font-weight:600; color:#222222;\"\u003eSize\u003c\/div\u003e\n\u003cdiv style=\"flex:2 1 300px; color:#333333;\"\u003e1\/2 inch\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"display:flex; flex-wrap:wrap; background:#ffffff; padding:8px 14px; border-bottom:1px solid #d9e8e6;\"\u003e\n\u003cdiv style=\"flex:1 1 220px; font-weight:600; color:#222222;\"\u003eConnection types\u003c\/div\u003e\n\u003cdiv style=\"flex:2 1 300px; color:#333333;\"\u003eO-ring push fit and BSP thread\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"background:#008377CF; color:#ffffff; font-weight:700; padding:8px 14px;\"\u003ePerformance (series 312, 3 bar rating)\u003c\/div\u003e\n\u003cdiv style=\"display:flex; flex-wrap:wrap; background:#f1f8f7; padding:8px 14px; border-bottom:1px solid #d9e8e6;\"\u003e\n\u003cdiv style=\"flex:1 1 220px; font-weight:600; color:#222222;\"\u003eSet pressure\u003c\/div\u003e\n\u003cdiv style=\"flex:2 1 300px; color:#333333;\"\u003e3 bar\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"display:flex; flex-wrap:wrap; background:#ffffff; padding:8px 14px; border-bottom:1px solid #d9e8e6;\"\u003e\n\u003cdiv style=\"flex:1 1 220px; font-weight:600; color:#222222;\"\u003eDischarge pressure\u003c\/div\u003e\n\u003cdiv style=\"flex:2 1 300px; color:#333333;\"\u003e3.6 bar\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"display:flex; flex-wrap:wrap; background:#f1f8f7; padding:8px 14px; border-bottom:1px solid #d9e8e6;\"\u003e\n\u003cdiv style=\"flex:1 1 220px; font-weight:600; color:#222222;\"\u003eRe-seating pressure\u003c\/div\u003e\n\u003cdiv style=\"flex:2 1 300px; color:#333333;\"\u003e2.4 bar\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"display:flex; flex-wrap:wrap; background:#ffffff; padding:8px 14px; border-bottom:1px solid #d9e8e6;\"\u003e\n\u003cdiv style=\"flex:1 1 220px; font-weight:600; color:#222222;\"\u003eMaximum flow rate\u003c\/div\u003e\n\u003cdiv style=\"flex:2 1 300px; color:#333333;\"\u003e142.1 kg\/hr\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"display:flex; flex-wrap:wrap; background:#f1f8f7; padding:8px 14px; border-bottom:1px solid #d9e8e6;\"\u003e\n\u003cdiv style=\"flex:1 1 220px; font-weight:600; color:#222222;\"\u003eMaximum boiler rating\u003c\/div\u003e\n\u003cdiv style=\"flex:2 1 300px; color:#333333;\"\u003e82.5 kW\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"display:flex; flex-wrap:wrap; background:#ffffff; padding:8px 14px; border-bottom:1px solid #d9e8e6;\"\u003e\n\u003cdiv style=\"flex:1 1 220px; font-weight:600; color:#222222;\"\u003eTemperature range\u003c\/div\u003e\n\u003cdiv style=\"flex:2 1 300px; color:#333333;\"\u003e5 to 110 °C\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"display:flex; flex-wrap:wrap; background:#f1f8f7; padding:8px 14px; border-bottom:1px solid #d9e8e6;\"\u003e\n\u003cdiv style=\"flex:1 1 220px; font-weight:600; color:#222222;\"\u003eMaximum static pressure\u003c\/div\u003e\n\u003cdiv style=\"flex:2 1 300px; color:#333333;\"\u003e10 bar\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"display:flex; flex-wrap:wrap; background:#ffffff; padding:8px 14px; border-bottom:1px solid #d9e8e6;\"\u003e\n\u003cdiv style=\"flex:1 1 220px; font-weight:600; color:#222222;\"\u003eNominal pressure\u003c\/div\u003e\n\u003cdiv style=\"flex:2 1 300px; color:#333333;\"\u003ePN 10\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"background:#008377CF; color:#ffffff; font-weight:700; padding:8px 14px;\"\u003eMaterials\u003c\/div\u003e\n\u003cdiv style=\"display:flex; flex-wrap:wrap; background:#f1f8f7; padding:8px 14px; border-bottom:1px solid #d9e8e6;\"\u003e\n\u003cdiv style=\"flex:1 1 220px; font-weight:600; color:#222222;\"\u003eBody and cover\u003c\/div\u003e\n\u003cdiv style=\"flex:2 1 300px; color:#333333;\"\u003eBrass, BS EN 12165 CW617N\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"display:flex; flex-wrap:wrap; background:#ffffff; padding:8px 14px; border-bottom:1px solid #d9e8e6;\"\u003e\n\u003cdiv style=\"flex:1 1 220px; font-weight:600; color:#222222;\"\u003eStem\u003c\/div\u003e\n\u003cdiv style=\"flex:2 1 300px; color:#333333;\"\u003eBrass, BS EN 12164 CW614N\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"display:flex; flex-wrap:wrap; background:#f1f8f7; padding:8px 14px; border-bottom:1px solid #d9e8e6;\"\u003e\n\u003cdiv style=\"flex:1 1 220px; font-weight:600; color:#222222;\"\u003eDiaphragm\u003c\/div\u003e\n\u003cdiv style=\"flex:2 1 300px; color:#333333;\"\u003eEPDM\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"display:flex; flex-wrap:wrap; background:#ffffff; padding:8px 14px; border-bottom:1px solid #d9e8e6;\"\u003e\n\u003cdiv style=\"flex:1 1 220px; font-weight:600; color:#222222;\"\u003eSpring\u003c\/div\u003e\n\u003cdiv style=\"flex:2 1 300px; color:#333333;\"\u003eStainless steel\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"display:flex; flex-wrap:wrap; background:#f1f8f7; padding:8px 14px; border-bottom:1px solid #d9e8e6;\"\u003e\n\u003cdiv style=\"flex:1 1 220px; font-weight:600; color:#222222;\"\u003eControl knob\u003c\/div\u003e\n\u003cdiv style=\"flex:2 1 300px; color:#333333;\"\u003eABS polymer\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"background:#008377CF; color:#ffffff; font-weight:700; padding:8px 14px;\"\u003eApprovals\u003c\/div\u003e\n\u003cdiv style=\"display:flex; flex-wrap:wrap; background:#f1f8f7; padding:8px 14px; border-bottom:1px solid #d9e8e6;\"\u003e\n\u003cdiv style=\"flex:1 1 220px; font-weight:600; color:#222222;\"\u003eCertification\u003c\/div\u003e\n\u003cdiv style=\"flex:2 1 300px; color:#333333;\"\u003eWRAS approved, CE marked\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"display:flex; flex-wrap:wrap; background:#ffffff; padding:8px 14px; border-bottom:1px solid #d9e8e6;\"\u003e\n\u003cdiv style=\"flex:1 1 220px; font-weight:600; color:#222222;\"\u003ePED category\u003c\/div\u003e\n\u003cdiv style=\"flex:2 1 300px; color:#333333;\"\u003eIV\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"font-weight:700; font-size:18px; color:#008377CF; margin:24px 0 10px;\"\u003eInstallation notes\u003c\/div\u003e\n\u003cp\u003eIsolate and drain the system before replacing a valve. Use the \u003cstrong\u003ecorrect sealing method for each connection\u003c\/strong\u003e: the push-fit end relies on its \u003cstrong\u003eO-ring seal\u003c\/strong\u003e and must be fully seated, while the BSP thread needs suitable jointing compound. Fit the valve \u003cstrong\u003ein line with the manufacturer installation instructions\u003c\/strong\u003e, run the \u003cstrong\u003edischarge pipework\u003c\/strong\u003e to a safe location and test the system for leaks. Confirm the valve is not installed where it can be isolated from the equipment it protects.\u003c\/p\u003e\n\u003cdiv style=\"font-weight:700; font-size:18px; color:#008377CF; margin:24px 0 10px;\"\u003eFrequently asked questions\u003c\/div\u003e\n\u003cdetails style=\"border:1px solid #008377CF; border-radius:6px; margin-bottom:8px; overflow:hidden;\"\u003e\u003csummary style=\"background:#008377CF; color:#ffffff; font-weight:700; padding:10px 14px; cursor:pointer;\"\u003eWhat does the Caleffi A312438 CST do?\u003c\/summary\u003e\u003cdiv style=\"padding:12px 14px; line-height:1.6; color:#333333;\"\u003eIt is a \u003cstrong\u003e3 bar safety relief valve\u003c\/strong\u003e that opens to discharge water or air if pressure in a hot water or heating system rises too high, protecting \u003cstrong\u003ecylinders, boilers and other components\u003c\/strong\u003e.\u003c\/div\u003e\u003c\/details\u003e\n\u003cdetails style=\"border:1px solid #008377CF; border-radius:6px; margin-bottom:8px; overflow:hidden;\"\u003e\u003csummary style=\"background:#008377CF; color:#ffffff; font-weight:700; padding:10px 14px; cursor:pointer;\"\u003eWhat connections does it have?\u003c\/summary\u003e\u003cdiv style=\"padding:12px 14px; line-height:1.6; color:#333333;\"\u003eA \u003cstrong\u003e1\/2 inch O-ring push-fit connection\u003c\/strong\u003e and a \u003cstrong\u003e1\/2 inch BSP thread\u003c\/strong\u003e. Check the thread type against your fitting before ordering, as trade listings differ on whether it is male or female.\u003c\/div\u003e\u003c\/details\u003e\n\u003cdetails style=\"border:1px solid #008377CF; border-radius:6px; margin-bottom:8px; overflow:hidden;\"\u003e\u003csummary style=\"background:#008377CF; color:#ffffff; font-weight:700; padding:10px 14px; cursor:pointer;\"\u003eAt what pressure does it open?\u003c\/summary\u003e\u003cdiv style=\"padding:12px 14px; line-height:1.6; color:#333333;\"\u003eIt is set at \u003cstrong\u003e3 bar\u003c\/strong\u003e. In the manufacturer series 312 data for a 3 bar valve, it discharges at \u003cstrong\u003e3.6 bar\u003c\/strong\u003e and \u003cstrong\u003ere-seats at 2.4 bar\u003c\/strong\u003e.\u003c\/div\u003e\u003c\/details\u003e\n\u003cdetails style=\"border:1px solid #008377CF; border-radius:6px; margin-bottom:8px; overflow:hidden;\"\u003e\u003csummary style=\"background:#008377CF; color:#ffffff; font-weight:700; padding:10px 14px; cursor:pointer;\"\u003eWhat temperature and pressure can it handle?\u003c\/summary\u003e\u003cdiv style=\"padding:12px 14px; line-height:1.6; color:#333333;\"\u003e\n\u003cstrong\u003e5 to 110 °C\u003c\/strong\u003e with a \u003cstrong\u003emaximum static pressure of 10 bar\u003c\/strong\u003e, for water and air.\u003c\/div\u003e\u003c\/details\u003e\n\u003cdetails style=\"border:1px solid #008377CF; border-radius:6px; margin-bottom:8px; overflow:hidden;\"\u003e\u003csummary style=\"background:#008377CF; color:#ffffff; font-weight:700; padding:10px 14px; cursor:pointer;\"\u003eCan I fit it myself?\u003c\/summary\u003e\u003cdiv style=\"padding:12px 14px; line-height:1.6; color:#333333;\"\u003eSafety relief valves are safety-critical. On unvented hot water systems the work must be carried out by a \u003cstrong\u003eG3 qualified installer\u003c\/strong\u003e, with the outlet piped to a safe discharge point.\u003c\/div\u003e\u003c\/details\u003e\n\u003c\/div\u003e","brand":"Caleffi","offers":[{"title":"Default Title","offer_id":67660359238022,"sku":"A312438-CST","price":13.7,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0958\/2051\/3629\/files\/Caleffi1-2O-RingX1-2inchMiSafetyValve-a312438-cst.jpg?v=1792476259","url":"https:\/\/qualityheating.co.uk\/products\/caleffi-3-bar-safety-valve-1-2-o-ring-push-fit-a312438-cst","provider":"AIZO Quality Heating","version":"1.0","type":"link"}