A system comprising a balloon catheter configured to be inserted into a body-part of a living subject, the balloon catheter comprising: an insertion tube having a distal tip; a force sensor connected to the distal tip; an inflatable balloon including: a proximal portion connected to the force sensor so that the force sensor is disposed between the distal tip of the insertion tube and the inflatable balloon; and multiple electrodes disposed around an outer surface of the balloon, and configured, when the balloon is inflated, to contact tissue at respective locations in the body-part; wherein the force sensor is configured to output at least one force signal indicative of a magnitude and a direction of a force applied by the balloon on the tissue when the balloon is inflated; a display; and processing circuitry configured to: receive contact signals from the electrodes; in response to the contact signals, assess a respective quality of contact of each of the electrodes with the tissue; compute the magnitude and direction of the force responsively to the at least one force signal; and render to the display a representation of a force vector and a representation of the inflatable balloon, responsively to the at least one force signal, while modifying a visual feature of at least one of the represented electrodes responsively to the respective quality of contact of the electrodes. an insertion tube having a distal tip; a force sensor connected to the distal tip; an inflatable balloon including: a proximal portion connected to the force sensor so that the force sensor is disposed between the distal tip of the insertion tube and the inflatable balloon; and multiple electrodes disposed around an outer surface of the balloon, and configured, when the balloon is inflated, to contact tissue at respective locations in the body-part; wherein the force sensor is configured to output at least one force signal indicative of a magnitude and a direction of a force applied by the balloon on the tissue when the balloon is inflated; a display; and processing circuitry configured to: receive contact signals from the electrodes; in response to the contact signals, assess a respective quality of contact of each of the electrodes with the tissue; compute the magnitude and direction of the force responsively to the at least one force signal; and render to the display a representation of a force vector and a representation of the inflatable balloon, responsively to the at least one force signal, while modifying a visual feature of at least one of the represented electrodes responsively to the respective quality of contact of the electrodes. receive contact signals from the electrodes; in response to the contact signals, assess a respective quality of contact of each of the electrodes with the tissue; compute the magnitude and direction of the force responsively to the at least one force signal; and render to the display a representation of a force vector and a representation of the inflatable balloon, responsively to the at least one force signal, while modifying a visual feature of at least one of the represented electrodes responsively to the respective quality of contact of the electrodes.