At my Jandy LXI heater and at the Aquapure 1400 the water temp shows one thing and my thermometer in the pool and the spa show about 7 degrees less. For example, today the thermometer in the pool/spa read 72 degrees. At the heater and SWG it read 79 on the LCD display. So when I turned on the heater for the spa it turned off but the water still felt cold. In my mind the thermometer is the right temp, not what the reading is on the equipment. Question is, is there some sort of calibration that needs to be done on this new equipment so the temp is accurate? Thanks