Flash Steam Properties


When water is heated at atmospheric pressure, its temperature rises until it reaches 212°F (100°C), the highest temperature at which water can exist at this pressure. Additional heat does not raise the temperature, but converts the water to steam.

By looking at the steam tables covered in the last lesson, we can see that at higher pressures more heat must be added to water (sensible heat) before it can turn to steam. Conversely, in a pressurized system, if sufficiently hot condensate is released to a lower pressure, some of that condensate will have the heat necessary to become steam. This is called flash steam.