I am using the Watchport/H sensor to get outside temperature and humidity. When it is just below the freezing point and down, the temperature returned is inaccurate. The temperature the sensor is giving me is actually higher than the real outside temperature. When it is above freezing point, it is correct. I checked this by using two other thermometers.
Here is some of the values:
The left columns is values from watchport, right column is the correct values.
The watchport sensor is connected to a pc using usb, and I use the ascii command interface to get the values.
SerialPort sp = new SerialPort("COM1");
string celcius = sp.ReadExisting();
What can be the problem?