savoc
27-08-2012, 06:19 AM
Hi guys have trouble with a unit. Comes up with code U4. indoor fan motor runs, checked all connections on indoor and out door unit. Green light on outdoor and indoor unit flashing. Voltages all appear all okay (3phase and neutral) Spoke to technical support waited 1/2hour. Support guy spent 1 minute on phone with me and said outdoor board needs replacing. Also he said check the fan motors, i asked for some resistance readings and said he could not help with that. I unpluged fan motors and checked from red to the other colours both motors had different readings. What readings should i have? Are there any test to check the outdoor board? this is a/c is not a inverter. Any help would be helpful.