Avent Digital Baby Bath and Room Thermometer accurate temperature, the philips avent digital bath and bedroom thermometer doubles as a convenient way to monitor the temperature both in baby's room and bath. Your baby will feel most comfortable in bath if the water is between 36.5 °C and 38 °C. A temperature of 39°C and above is too hot and your baby could get burned! At a room temperature of about 18°C babies feel most comfortable when sleeping.