In terms of control, a linkage device must be added between the fan and the heater to ensure that the heater starts after the fan starts. After the heater stops working, the fan must delay working for more than 3 minutes to prevent the heater from overheating and damage. The single circuit wiring must conform to NEC standard, and the current of each branch shall not exceed 48A. Generally, the gas pressure heated by the channel heater shall not exceed 0.3kg/cm2. If the above pressure specifications are to be exceeded, please select the circulating heater. The high temperature of Zui heated by low temperature heater is not more than 160 ℃; the medium temperature heater is not more than 260 ℃, and the high temperature heater is not more than 500 ℃.