I have the Circupool si-45+ and when I fired it up for the first time this year it ran for a few minutes and immediately went into a low salt, check cell mode. My water temp here in Louisville is only about 61 degrees according to the Circupool readout. This unit continously shows the salinity on the readout. It says 3000 ppm. You can scroll through the menu and get a instant readout of the current salt level. The readout on there shows 0000. I tested my salt level with a test kit and it showed 1400 ppm. I am curious if the low temp of the water has any bearing on the actual level of the measuring of salt in the pool. I closed last year at 3000 ppm. Unit was installed last July and performed flawlessly through the rest of the season. Did not do any significant draining of the pool during the winter. The check cell readout has a feature where it flashes every 3 months for inspection. It currently shows a solid light. The current levels show the unit is not producing chlorine, which is normal based on the current salt level.