Hot air curtains provide for airflow resistance through openings irrespective of the absence of any such barriers. It is equipment that is fan powered creating an invisible barrier or wall separating two environments of different nature. One could be hot/warm and another very cold. The distinct advantage of these curtains is that they do not inhibit human traffic movement. The use of curtains in buildings has been ascertained to be very effective especially in buildings that have large numbers of people moving in and our constantly.
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These curtains have also been associated with great energy savings because the cost of heating and cooling rooms is decreased. The climate in such rooms is constantly at the required temperature with no fear of air conditioners breaking down. Insects are also kept at bay and draughts are eliminated by these curtains. When selecting a curtain it is essential to consider things like height of installation, door width, interior décor of the building, power voltage available, and of the doors are manual, always open automatic or revolving. Other important aspects to look out for include number of doors in a building and the areas they are situated.
The hot air curtains are able to discharge hot or warm air waves in three ways. The first being they can discharge the air waves from the top to the bottom of the building, or from one side of the room to the other and finally from the below to the top. For a curtain to be considered effective, it needs to perform its intended function with speed and at large volumes. This helps keep the room at the intended temperature without faltering. If the room is large in terms of width and length then the speed will be much slower than with a smaller room. The temperature will be kept at the appropriate desired level but much less effectively in a larger room as opposed to more effectively in a smaller room.
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For air discharges that are from the top to the bottom of the room then a horizontal installation is most effective. The warm or hot air waves are discharged towards the floor or bottom of the room where the curtain is installed. Installing on the sides of the entrance of a room or building will result in achieving the side by side flow of hot or ht air. They can be installed on one side of the room or on both sides of the room. Thermodynamics collaborates the fact that air curtains releasing air from bottom to top are more effective than their counterparts. The unfortunate case is that they are rarely used because of their cost and complicated nature.
Two types of hot air curtains exist in the market. The recirculating curtains that are commonly used in supermarkets because of their low velocity means of discharging air waves. The non recirculating curtains are cheaper and easy to operate. The first latter is more costly to set up, operate and maintain. This is due to the constant filtering process. During installation a grill is installed at the entrance and filter on the opposite side of it. The later type however, has not costs associated with it because the air discharged does not need to be filtered. They emit high velocity air waves rendering them more effective.
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