I'm not sure if I'm in the right forum area. I worked on a heat pump air conditioning unit the other day and the communicating control board was flashing a code saying it was on high pressure lock out. After checking all the basics nothing showed obvious as to what was the problem. I disconnected the power supply to the control board to see if it would reset and it did. I decided that it was the control board itself and replaced it. The person did not have the problem again before I changed it but just to be sure I replaced it anyway as it is under warranty. What do you think the problem is???