lower the resistance of the 10k NTC thermistor (orange) to simulate temperature increasing. As the temperature increases, the common anode RGB led will change to indicate:
blue: too cold
green: just right
red: too hot
Bath water temperature for washing babies has to be body temperature or they get upset or cold or burnt.
The resistance divider network will probably need to be picked by trial and error depending on the thermistor being used, and calibrated with a real thermometer. if you have mixer taps like I do, the thermistor can be a probe that can be placed right up inside the tap/faucet so you can get the running water temperature set correctly before filling the bath, instead of faffing about with hot and cold etc etc dear god this is a pain in the ass