In this video we're going to show you how to replace the MRCOOL air handler control board within your unit's air handler. Before getting inside the air handler, you will want to make sure that the power is turned off from the main power source at the disconnect box. The first thing you will want to do it remove the electrical covering. Next, disconnect the display board. To remove the casing, you will need to remove some screws. In this model, there are two visible screws. There may be more screws depending on the sized unit you have. For the hidden screw, there is a small plastic covering that needs to be lifted for access. When the screws are removed, pull the covering from the top clips. The cover should then come free. On the right side of the air handler, there is a metal box that encases the control board. Remove the screw holding the box in place. Then pry the box from the clip holding the box in place. The box will still be connected to the air handler, so you need to remove the plugs from the MrCool air handler control board to free it completely from the air handler. Remove the metal coverings. Open the black box to reveal the MrCool air handler control board. The control board is held in by two clips, which are marked by two white squares. Press the clips to remove the control board and remove any wires connected to the black box. Once you receive the new MrCool air handler control board, place it in the black box and replace the coverings. Make sure all your connections are secure. Replace the air handler covering and you are finished. Now that the new MrCool air handler control board is in place, there should no longer be an error code. For any questions, contact MRCOOL support.