The free float steam trap does not have any levers or joints inside. The float is the only moving component. The floats used in this type of steam trap are made of high quality stainless steel with very low dimensional tolerances.

When steam enters the trap, the entrained cold air is first discharged from the exhaust valve port. Subsequently, the condensed water enters the steam trap, and buoyancy causes the float to rise, thereby opening the drain valve and allowing the condensate to drain. Equipment (heat exchangers, etc.) has reached a higher operating temperature due to condensate discharge. At this point, the condensate and steam enter the trap together, and the heated air closes the exhaust valve port, preventing steam from escaping. Thereafter, the float can be adjusted according to the flow rate.

In order to prevent steam leakage in the steam trap, in addition to the metal-to-metal connection to provide sealing, the water level maintained on the drain valve can also provide a good water seal.

For condensate drain on the drum dryer, a bypass line is required above the trap to allow steam to escape before entering the trap to prevent steam locks from occurring.