Richard,

The info I have for the FM25AH-UE0 shows 2 compressors. A question, does the front panel have a sticker 'MPS inverter' ? This indicates it is a 'multi power system' and will have multiple compressors. I still suggest starting with the service software. This will indicate all parameters in the system. If you have a laptop and LG are not willing to attend site I would pressure them to supply it to you. It is quite simple to operate and understand. It comes as 2 parts - Cable and module box - software and hard lock key.