"Used in a central heating system to stop a back flow around boiler piping. Works fine, easy to fit took ten minutes, with a lot more time draining and refilling the system. For which I can't blame the fitting ! As for reliability 48 hours it's a bit hard to judge ! Strange question on something you have just fitted."
"OK solid check valves, but the rather small flat areas on the barrel sides are not the best I have used for getting a grip on with a spanner or wrench when tightening the compression joints. Aok once fitted."