Dehumidifiers work much like air conditioners; the warm moist air is drawn into the dehumidifier by a fan and the moist air then crosses over the dehumidifier's refrigerant cooled coils causing the moisture in the air to condense on the coils within the machine and is then collected in to a tank for disposal.
 
Dehumidifiers are used for a number of applications and help reduce humidity levels making you less hospitable to allergens, dust mites, mould and mildew and also help speed up the drying process of newly plastered rooms.
 
Used extensively following flooding or water damage a dehumidifier when placed in an affected room will when used within its operating temperature range effectively remove excess moisture. Another great use for a dehumidifier is for drying Plaster or Artex allowing you to finish decorating the room even sooner.
 
Whilst a dehumidifier on its own can be very effective it is worth considering using a heater and or an air mover or carpet dryer at the same time to speed the process.