Performed semiannual maintenance on one heat pump cooling system. Inspected all performance, mechanical and safety systems. Flushed and treated the primary drain line and cleaned and washed the outdoor condenser coils to remove all dust and dirt from fins of coils. I found that the compressor plug wiring harness was resting on top of the suction line at the outdoor condenser, rubbing through the insulation. I went ahead and placed a foam wrap around the piping and secured the wiring harness to prevent a high voltage rubout onto the refrigerant piping. No major issues were found. Everything is working at this time.