Best espresso machine with PID PID can be described as an electronic gadget that can increase the temperature gradually in order to achieve an ideal temperature. Heating elements that are not PID will warm the machine up at the temperature desired however due to the thermal inertia, the boilers are heated to the temperature desired continuously. Baristas at home have devised specific routines to get around this problem and these are known as temperature surfing. A PID will heat it for a brief time, and then takes a measurement of the temperature. The lower the boiler's temperature, the higher the rate of temperature increases. The closer that SET The temperature is, the less the increases. If the boiler is overheated the espresso shot could over-extract, and the result will be bitter. A PID can ensure the best extraction temperature for your espresso shot. There is another reason. Once you're comfortable altering the beans you roast, you'll nee...