Duct heaters and Infrared heaters

Posted by qualitytravellinkexchange@gmail.com on July 13th, 2018

The duct heaters are manufactured in different dimensions and their types are tubular, open coil and finned tubular which are inserted or flanged. Air duct heaters have their applications in comfort heating /ventilation systems whereas process duct heaters have their applications in industrial process heating systems such as ovens which need forced circulation or re-circulated air.

Duct system is included in air distribution system in order to make a controlled way for the air to flow. These duct systems are used for air circulation in factories, commercial buildings, home etc and are located within the ceilings, floors, walls etc. It has a network of rectangular/round tubes made of insulated plastic, fiberglass duct board or sheet metal.

Another type of duct heater is Electric duct heater which warms the air passing through the duct using electricity. Conversion of electricity to heat is done using a heating element and heat is transferred to air using convection/conduction. Electric duct heaters are used for primary, supplementary and space heating applications.

Electric heaters are efficiently used in cold rooms as they monitor temperature and modify heat output to maintain temperature of open coil element. These heaters are able to heat a place at a particular time thus maintaining efficiency.

Electric heaters can be installed in schools, power plants, churches, waste water facilities, office buildings etc and are easy to install due to their design. These heaters have features such as air-flow cut-off and thermal cut-off. Air flow cut-off ensures equal flow of air to all the heating elements and thermal cut-off is of two types: primary and secondary. Primary thermal cut-off stops the unit when temperature limit has reached and secondary thermal cut-off enables the personnel to stop the unit when temperature limit is reached.

Electric heaters are also used in petro-chemical/ chemical installations and ship construction as they control temperature.

Infrared Heaters

Infrared heaters burn fuel to produce heat which radiates objects like building components, machinery, floor etc and also people in that area. There are three types of Infrared heaters known as short wave, medium wave and ceramic infrared heaters.

Shot wave Infrared heaters: These heaters transmit heat at 300000 km/sec (approx.) of velocity similar to speed of light. These heaters are used for applications with dust free conditions and vacuum. These heaters have some advantages such as

• Infrared waves directly deliver heat to material by penetrating it.
• Loss of energy for heating media and heat loss due to convection are eliminated as heating is done by radiation.

Medium wave infrared heaters: These heaters include a resistance wire enclosed in a Quartz tube with outer diameter of 8mm. The Quartz tubes are mounted in a housing and are placed parallel to each other. These heaters find their applications in

• Thermoforming
• Drying paints and lacquers
• Plastic forming
• Curing rubber
• Shrink packaging tunnels
• Laminating
• Drying textiles

Ceramic Infrared heaters: These heaters generate maximum output of heat energy as they have a heating coil that is firmly burnt in and has a heat-proof resistance wire for protection against damage.