Duct heaters heat the moving gas streams where it is installed right in the center. It is well protected through wrappings preferably made of incoloy, iron, aluminum, steel, and stainless steel. Insulation material provides an additional shield to make them strongly bear any type of environment. These materials are either made of ceramic or mica or mineral or fiberglass.

Specifications
The specifications of the Electric duct heaters are as follows:

• Duct depth for the installation of the heater
• Duct height
• Duct width
• AC voltage
• Heat capacity, that is, density of the watt

Features
Characteristics of a electrical duct heater are equally important to notice since they define the specialty of this kind of heater.

• Has the rare option for cooling
• Heat transmission is aggravated by using fans
• A built-in thermostat which adjusts either in integrated or separate form
• Have the facility of a thermocouple installation
• Explosion-proof enclosures, suitable for all kind of environment
• Available in varied design or configuration
• Constructed from corrosion resistant material
• Facility of insulation option.

Advantages
Duct heaters have an extra edge when compared to electric heaters which are:

• No threat from the corrosive weather as the coil is protectively wrapped.
• Open coil is devoid of fragile ceramic insulators.
• Open coil is strong & is less susceptible to corrodes.
• High temperature preferable for the operation of finned tubular.

Applications
Just like other heaters, a duct heater has its own set of areas where it's demand is high.

• Used for process and comfort heating ducts
• Drying & producing warm rooms
• Forced air dryers
• Recirculation of ovens
• For dehumidification
• Forced air comfort heating
• Air heater booster
• Re-heating
• Annealing
• Core drying
• Make-up heating
• Pre-heating of the air
• Air handling accessories
• Fan coils
• Reheating of the terminal
• Heat pump auxiliary systems
• Multi-zone reheating