HVAC system design : insulation of ducts for energy efficiency
HVAC SYSTEM DESIGN : INSULATION OF DUCTS FOR ENERGY EFFICIENCY
Duct insulation is a major consideration because it ensures that the air flowing inside the duct will stay at the desired temperature and won’t leak out.
When the air leaks out then there will be unnecessary energy loss, which means the system consumes more power to deliver the air at the required condition, which is not good for the environment. Without proper insulation of ducts, the air inside the duct will heat up quickly and blow out hot air. A proper duct insulation can prevent temperature drop, condensation build up and make sure that regulated temperature is maintained in the desired space. Proper insulation can also prevent condensation in ductwork as cool air flowing through warm air in space causes condensation. Flow of cold air into the space is caused by poor insulation. These condensation leads to mould growth and foul smell which is not good for health.
The proper insulation of the duct comes from sealing all the leaks before adding the insulating materials. There are many materials used for sealing the leaks in the duct. Predominantly fiber glass insulation materials are used for insulating the ducts.
Ductwork are used to reduce the noise that are generated when the HVAC system runs. The noise that are produced in the duct are due to the air turbulence which are produced in the system. It propagates through the duct which make the people in this surrounding uncomfortable. The cause of noise generation is due sudden change of the airflow path, from straight line to sudden bend, and due to the friction produced between the duct material and the air. The noise can be reduced by using proper lining of sound absorbing material and using vanes at the bend and by using proper insulation material, as excess noise produce unwanted vibration in the building. The noise produced in the structure are due to the mount of the system this structural vibration can be avoided by using suitable flexible fittings which can isolate the vibration produced in the duct from the structural element of the building in which they are fixed.