How to connect the water pipe to the car heater: there are two valves on the engine body, which are connected to the water inlet and outlet pipes on the heater respectively, and then the valves can be opened. The working principle of the car heater is to use the water from the engine, pass through a valve, flow through the radiator of the heater, start the fan, and the heat of the engine will be dissipated into the car. It can work at any temperature. And the heat dissipation can be adjusted, and the principle is the valve. This valve is related to the temperature adjustment switch on the air conditioning panel. By adjusting the opening of the valve, the flow of water can be adjusted, so as to achieve the purpose of adjusting the temperature.