The large O-ring under the LN clamping nut is the main sealing element ensuring the watertightness of the end of the UV sterilizer. Without this ring, water would leak around the axis of the quartz tube and could seep into the electrical part of the device.
The ring is made of a material resistant to UV radiation, chlorinated water and the temperature fluctuations of seasonal operation. The precise diameter matches the standard LN nut used on pool UV sterilizers.
At every UV lamp replacement, we recommend replacing both O-rings (small and large) at the same time as a preventive measure. This prevents unexpected leaks during the season and ensures safe operation of the electrical device near water.
