A dehumidifier is used in buildings to reduce the levels of humidity in the air for comfort, health and safety or to eliminate unpleasant odours that are caused by excess moisture in the air. Water collected from the air is then discarded, leaving a fresher, safer environment to live or work in. There are three main types of dehumidifier available, Refrigerant, Desiccant and Whole house dehumidifiers. Refrigerant humidifiers draw water from the air through a fan to a cooled metal plate. Desiccant humidifiers absorb water from the air using a desiccant and Whole house humidifiers are used to remove moisture from the whole home through a ventilation system. These ventilation systems can be designed on a much larger scale for industrial applications. Dehumidifiers are used not only to provide comfort to the habitants or workers in buildings but also in industrial applications where the control of moisture is essential. They are used in various processes such as climatic chambers for water treatment, grinding and machining, food production, packaging and printing.