Mainly used for air heating in air ducts, the specifications are divided into three forms: low temperature, medium temperature, and high temperature. The common structural feature is the use of steel plates to support the electric heating tube to reduce its vibration, and the junction box is equipped with an over temperature control device.

In addition to installing over temperature protection in the control aspect, a connecting device is also installed between the fan and the heater to ensure that a differential pressure device is added before and after the electric heater starts after the fan starts to prevent wind failure. The gas pressure heated by the channel heater should generally not exceed 0.3Kg/cm2. If it is necessary to exceed the above pressure, a circulating electric heater should be selected; The gas heating temperature of the low-temperature heater shall not exceed 160 ℃; Medium temperature type not exceeding 260 ℃; High temperature type not exceeding 500 ℃.

Air duct electric heaters are used in industrial air ducts, air conditioning ducts, and various industries to heat the air and increase the temperature of the output air. They are generally inserted into the transverse opening of the air duct. According to the working temperature of the air duct, it is divided into low temperature, medium temperature, and high temperature; According to the wind speed inside the air duct, it is divided into low wind speed, medium wind speed, and high wind speed.