A steam trap simply allows condensate (condensed steam aka water) to pass while holding back (or trapping) steam.  Steam traps vary in shape and size and should be selected for the application and flow rate. A good steam trap in the wrong application or a malfunctioning trap can wreak havoc on your system.  A steam trap that has gone bad may stick open or closed, neither of which is a good situation. As one of the few moving parts in your steam system, it is important to perform regular steam trap surveys to keep your system at peak efficiency.