After several weeks of valve operation at media temperatures < 0° C, there may be a reduction in valve stroke due to ice formation, depending on the operating conditions, such as ambient temperature and humidity.
In case the valve is used as a 2-port valve, this stroke reduction leads to a reduction of the valve’s kvs value. In case the valve is used as a 3-port valve, it leads to leakage on port B, as it cannot be fully closed anymore.
It is important to note that this does not cause any damage to the valve. However, if these effects pose a concern or an issue, it is recommended to defrost and dry down the valve before restarting operation.