I've got an Aquapure 1400. Love the thing. This summer, salt sensor in the system measured between 4.1 & 4.2 all summer. I did not add any salt and figured salt level would decrease to normal soon enough, but it never did. Then we got a sudden cold snap here in AZ and salt concentration (as measured by the Aquapure sensor) suddenly dropped almost overnight to 2.3. I used a salt strip to measure level, and it said it was way high, but not sure I can trust those results either. Any chance the Aquapure sensor's accuracy is affected by air/water temp?