Preparatory work and performance influencing factors for car heater
Factors affecting the performance of car heaters:
1. Increasing the gas inlet flow rate of the parking heater can enhance the convection heat exchange of the parking heater, and reduce the surface temperature of the electric heating element in the parking heater, which is not only conducive to prolonging the service life of the electric heating element of the parking heater , And reduce the heat loss of the parking electric heater, so the power of the parking heat exchanger is improved, but if the speed is too high, the pressure loss will increase sharply, which will not be conducive to the improvement of heating power.
2. If other conditions remain unchanged and the external load is changed, the wall temperature of the electric heating element in the parking heater will change linearly. If the external load increases, the wall temperature of the electric heating element will increase, which will decrease the temperature of the parking heater. The service life of the electric heating element, but if the external load is too small and the wall temperature is too low, the power of the parking heater heat exchanger drops again, so the selection of the external load of the electric heating element in the parking heater is more important.
3. When the final parking temperature T2 in the parking heater increases, due to the increase in parking viscosity, the gas Reynolds number decreases, which reduces the convection heat transfer intensity, and the surface temperature of the electric heating element in the parking heater rises at the same time, causing loss of heat dissipation Add and then drop the power of the heat exchanger. When T2 progresses too much, the surface temperature of the electric heating element will also increase greatly, making the general electric heating element unacceptable. Therefore, the addition of T2 is usually restricted by the heat resistance function of the electric heating element material in the parking heater.
Preparation work before installation of parking heater:
1. Check the integrity of the parking heater before the equipment, and unscrew the pipe buckle and plug;
2. The receiving (water pipe and steam pipe) connecting the parking heater should be the same size as the inlet and outlet pipe joints of the radiator, and the receiving cannot be used to support the radiator;
3. When the parking heater uses steam as heat. Foreword, the steam is introduced about ten minutes before the fan starts to preheat the radiator to prevent the steam from entering the cold radiator suddenly and generating a large amount of condensed water and impacting the equipment;
4. When the air inlet pipeline of the parking heater is directly connected to the outdoors, a blocking device should be installed at the air inlet to prevent the radiator from being frozen when it stops working;
5. Before installing the equipment, you should see clearly that the inlet end of the steam inlet is the end of the finned tube with shrinkage holes;
6. The backwater receiving end should be equipped with a steam trap, and the drainage volume of the steam trap should exceed 3 to 4 times of the condensed water volume of the radiator;
7. The parking heater shall be equipped with corresponding heat medium pipeline system according to the architectural design. Note that gate valves should be installed on the steam or hot water pipeline and on the return water pipeline; when heating with steam, a condensate sweeper should be installed on the condensate pipeline. When several radiators are used in combination, each one can independently control its steam inlet, exhaust and return pipe equipment, especially when the air is used in series in the air flow.