ductless ac/heat burnt black wire at indoor unit

[mburns1025]

Have a ductless ac/heatpump 120v past 7-8 years and recently the black wire on indoor unit is roasted at the terminal....any ideas where to look or should I just beef up the wire to maybe 10-12 gauge intead of the normal 14 that comes with kit...unit is fused correctly at 15 amps both in at fuse box and at outside disconnect-which I think also popped...gotta check when i get home...thanx

[ahh-cool]

usually if the terminal burns it is because a motor is going bad. It could also be a loose connection