The code is NO CO. If you have THAT code, the refer is locked out and will not work on any power source. A NO CO code shuts down all refer and control board operation. Your unit is 12 years old. IF no Ammonia leakage, the most common cause of a NO CO on older units is the rear cooling fans are not working. A Unit that old the odds are the fans are worn out and will not work. The Fan Tstat is probably bad also. Replace BOTH fans and the Fan tstat. The bad news is---you must pull the refer to even check fan operation if you do not hear those fans running. Unless the refer is in a slide room, then you can check the tstat and power thru the tstat from the outside upper vent door. You will have to do a HARD NO CO reset. But THAT will be useless to do until you find and fix the cause of the NO CO problem. What is the outside temp where you are located? Doug
