As the telescope plus building rotates as a whole, a rotary valve exists at the base of the telescope to allow water for the cooling system to circulate. In the center of this valve there is a small hole which is used for things like the fiber connection between the computers in the control room and the outside world. In the current valve, the central hole is completely filled, and more space is needed (e.g., for the fiber which connects the telescope with FIES when it is installed in its new housing). For this, a new rotary valve was designed which has a larger central hole. The new valve is currently being assembled and tested.