It may very well be that the compressor is shot on this unit even tho it was hardly used.. If you're skilled with using a volt tester then disassemble the unit exposing the wires to the compressor terminal and check for power with the controls turned to cool... If power is getting to the compressor and it's not running then it's shot... Another way is to disassemble and simply run the unit on cool for a 1/2 hour or so and just feel the compressor being mindful it may be very hot... This could indicate the compressor is being powered up but can't run so the motor inside gets hot to the touch... Finally, if power is not measured at the compressor in the cool cycle then most likely it's the control like you first diagnosed... cheers kooler