When purging pipelines, do water pipes without pressure-boosting equipment in the water tank need to be equipped with solenoid valves?

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I have a question: In the water circuit, a water tank is used along with a pressure pump to supply water, while in the air circuit, an air compressor provides air at a pressure of around 0.6 MPa. The air supply valve at the end point is closed, and the air circuit is switched to the water supply pipe for purging, in order to remove water from the water pipe and prevent freezing. As shown in the diagram, the water pipe is equipped only with a manual valve and a check valve. When the solenoid valve for air purging is opened, since the water circuit at the end point is an open system, the compressed air flowing at a speed of around 25 meters per second will create negative pressure in the water pipe, causing the water in the tank to keep flowing out through the check valve continuously It is still the pressure of the gas that causes the check valve to close; in this case, there is no need to install an electromagnetic valve in the water circuit