As the name suggests these fans run continuously! They are the most effective method of ventilation as the air is constantly refreshed - this is particularly important in areas of high useage or those rooms that have no 'rapid' ventilation method such as rooms without windows. At only 10 to 14db the CV100 is as silent as a fan can get and its power consumption is a miserly 2.2 watts at 10l/s airflow. Enhanced by the introduction of a discreet white fascia in place of the traditional grille, the fan is designed to blend into the background. As an alternative to the standard AC version the low voltage 24v model provides an additional level of safety for operation in a moist or wet environment. Safety Extra Low Voltage (SELV) fans have been designed for increased safety when installing fans within a bath or shower spray area. SELV fans have an isolating transformer(which is located in an area away from the fan) and reduce the voltage to 24v so that in the unlikely event of a fan fault the electrical charge is at a safe level. SELV fans are the safest option for use in 'wet' areas offering increased peace of mind and have a safety rating of IP24 The CV100SV fan can be wall or ceiling mounted or fitted as an 'in line' installation