Steam trap

• Steam is formed when water vaporizes to form a gas. 
• This is done by giving latent heat of vaporization to water. 
• By this water will convert into vapor. 
• When the work is done (i.e. steam has given up its latent heat), steam condenses and becomes condensate. 
• Now the condensate will not be able to work same as the steam. 
• So now the thermal efficiency will reduce as efficient steam is mixed with the condensate.