I received this distiller to use for water. There was a resistor in a sealed packet in with the parts. I believe resistors are used to control the temperature. I didn't know if it needed to be installed. I spent two hours trying to research it. I tried to send a message to the manufacturer, but it was not accepted. I checked other distiller companies, but they didn't include this part. I tried using it twice so far. It takes an hour less than my old distiller and holds a little more water. It seems to work very well, but the water spout does not match up with the water tank, so make sure you get it in the right spot.