http://www.adencn.com/Energy recovery ventilation (ERV) is the energy recovery process in residential and commercial HVAC systems that exchanges the energy contained in normally exhausted air of a building or conditioned space, using it to treat (precondition) the incoming outdoor ventilation air. The specific equipment involved may be called an Energy Recovery Ventilator, also abbreviated ERV. Ductless ERVs provides fresh air, recovers the heat to save energy, and doesn't need ducts running to each and every room in the house. Commercial Energy Recovery Ventilators (ERVs) are the best choice for ventilating your home or workplace. These units are designed to provide fresh air into the building while exhausting an equal amount of stale air to the outside. Heart rate variability (HRV) is the physiological phenomenon of variation in the time interval between heartbeats. It is measured by the variation in the beat-to-beat interval. An air curtain is a fan-powered device that creates an invisible air barrier over the doorway to separate efficiently two different environments, without limiting the access of the people or vehicles. Centrifugal Air Curtains are highly acclaimed for their tough construction and low maintenance, showing fire prevention performance. These air curtains are specifically designed to maintain the temperature, hygiene and humidity during traffic movement through the doors. A fan filter unit (FFU) is a type of motorized air filtering equipment. It is used to supply purified air to cleanrooms, laboratories, medical facilities or microenvironments by removing harmful airborne particles from recirculating air. The units are installed within the system's ceiling or floor grid. Large cleanrooms require a proportionally large number of FFUs, which in some cases may range from several hundred to several thousand. Units often contain their own pre-filter, HEPA filter and internally controllable fan air distribution. As the name implies, ventilation fans are used to ventilate a residential or commercial space. This works to bring fresh air from the outside and into the enclosed space. It helps circulate air through the building or home, which prevents individuals from breathing stuffy, less oxygenated air. Without ventilation, you and other individuals will be left breathing air that is not fresh. At its simplest, a duct fan (also known as an inline duct fan or simply an inline fan) is a fan that is installed inside of a ventilation duct, rather than at the end point of a duct or through a wall. However, there are many variations of duct fans, and these should be understood before deciding whether or not this is a good way to meet your ventilation needs. Rectangular duct fan are intended for ventilation of medium size and large rooms where space is limited. The DV-SQ duct fans have been designed and manufactured in order to ensure the high efficiency, failure-free operation and direct connection to the ventilation duct.