What is the purpose of steam traps in a steam heating system?

Steam traps automatically remove condensate and non-condensable gases from steam systems while preventing live steam loss. They maintain heating efficiency by ensuring heat transfer surfaces contact steam (not condensate), prevent water hammer (dangerous pressure surges from condensate slugs), remove air and CO2 (which reduce heat transfer and cause corrosion), and protect equipment from condensate accumulation. Types include mechanical (float, bucket), thermostatic, and thermodynamic traps.