A system for treating tissue comprising: a radio frequency power source (6) to provide radio frequency power a fluid source (1) to provide an electrically conductive fluid an electrosurgical device (5) configured to provide the radio frequency power and the electrically conductive fluid to tissue a flow rate controller configured to control the flow rate of the fluid based upon the amount of radio frequency power provided from the power source to the electrosurgical device and without feedback from the tissue and a switch (13) to prime the system before turning on the radio frequency power source (6).
