Marc, The YG2800i control unit (price checked $634.32) looks to be damaged. How does this happen? Most likely by using 14 or 16 gauge extension cords to power refrigerators/freezers/pumps/furnaces, especially destructive when using 50 , 75 or 100 foot long ones!! Refrigerators need a much more expensive high quality brand name 12 AWG (gauge) extension cord to safely start the compressor and fan including whatever else is daisy chained on the same line consuming power. BTW, the lower AWG numbers have larger diameter copper wiring, need to transmit full power without a current increasing voltage drop. Always use the shortest extension cord as possible -and- do NOT use one where the female plug end feels loose when a male plug is inserted too easily. That signals bent/worn terminals that now are making contact too loosely with the refrigerator/freezer's plug, causing arcing/sparking voltage spikes when a very heavy starting load is applied. Also, do NOT neatly coil up any excess length of power cord in a circle as it will waste power as an inductive coil, evidenced by the heat it will give off!
I prevented such component damage to my neighbors equipment during our hurricane Irma 46 hour power outage. He was using a 50 foot 14 AWG extension cord to connect the EF2000iS to a LARGE kitchen refrigerator about 18 feet away. Better, but not ideal was substituting the 50 for a 25 footer at the start of the outage.
On Gennys that hook up RVs or home hook-ups with the 30 or 40 Amp sockets, you need to use 10 gauge wire.