Mechanical

        Mechanical steam traps function based on a simple principle of physics. Steam rises inside the trap, and the pressure forces the Valves at the bottom of the trap closed. At the bottom of the trap is a weight that, when enough steam has changed to water, will float and open up an escape valve for the water to drip out. The most common style of mechanical steam trap is referred to as the inverted bucket, because of its shape.
    Thermostatic

        The thermostatic steam trap functions based on changes in temperature rather than pressure. This type of trap has a  Valves that contains a bi-metallic material which, when heated above a certain temperature, will expand and keep the release valve closed. When the temperature drops, the bi-metallic material will shrink and open up the valve to allow the steam that's condensed into water to drip out of the steam trap. Thermostatic steam traps must be carefully calibrated, because increased pressure can affect the temperature in the trap and affect the trap's function.
    Fixed-Orifice

        A fixed-orifice steam trap is one of the less commonly used types of steam trap. Unlike the other traps, which have a regulating mechanism that controls the release of water, a fixed-orifice steam trap is constantly open and discharging water. It is, in effect, just a hole carefully placed in a spot in the steam trap. Fixed-orifice steam traps should only be used in situations where there is a constant level of steam load, because if there is a variable steam load, a fixed orifice will either allow steam to escape or cause water to back up into the system.