Arrived on site to perform diagnostic on system. Homeowner states he didn’t feel any air flow coming from the vents the other day. System has been working fine but would like it checked. He replaced a couple things on it already himself. Cycled system for cooling. Unit kicked on and started cooling normally. Checked indoor and outdoor unit electrical and system components. Secondary motor controls are in range. Both motors indoor and outdoor are brand new. Cycled system on and off number of times and unit kick on correctly every time. Blower door was loose, and it is very possible that door would disengage the door switch and unit would not kick on. Circuit board could also have an intermittent internal fault. Unit is working correctly at this time so very hard to pin point a issue. System is operational upon departure.