The main control brain of the floor heating is on the sub-catchment, so first look for it from the sub-catchment. Generally, there is a dedicated air release valve at the top, which can be connected with a hose first, and then the other end goes into the sewer, and slowly find the open air You will hear the sound of sizzling air out of the valve until there is a steady stream of water flowing out, and then close the air release valve. Note here that the air release valve is opened in the counterclockwise direction and closed in the clockwise direction.
