My unit worked for about 3 weeks before the refigerator started getting warmer and warmer. Freezer iced up on inside cover. Repairman didn't check with meter but defrosted unit and said the main board is bad and probably UI board. Is this a symptom of the board and should I try to diagnose myself? Unit's been working great for about 24 hours.
Answer Hello Bluwho. It sounds like you may have a defrost problem with the unit. Check and see if there is any frost build up on the back wall of the freezer. If so, you will need to test the defrost heater and the defrost thermostat. They should read closed for continuity when cold. You can test this with a multi-meter TJMA-DMT3. I will include a link at the end to assist you how to use the multi-meter if needed. If both parts are good, you will need to replace the defrost timer. Once the problem is repaired, you will need to thaw out the ice on the coils before the unit will operate properly. http://forum.appliancepartspros.com/oven-repair-including-ranges-cooktops/4810-how-check-continuity-ohmmeter.html
Can I do it myself? Install the main control board I mean.
Answer Hello Bill,
The main control board is not hard to replace. It is located in the bottom of the unit inside the plastic control board housing. Just make sure the power is disconnected and the wires are placed on the new board where they were on the old board. I recommend to only remove one wire at a time and put it on the new board. Then remove the next wire and place it on the new board. This will prevent crossing any wires. Also, this board is static sensitive so it isn't a bad idea to use a grounding strap during the board replacement.
The fridge and freezer cool to proper cooling temperature and when the motor kicks off it does not kick back on. Is this the control board?
The control board could be the issue but you would want to check the thermistors on the unit to ensure that they are within range first. At 77 degrees the thermistors should read 2.7K ohms. If not reading this then they are bad and need to be replaced. If they do read this then the control would most likely be the cause.