Hello, I am new to this forum and a new home owner. Thank you for this service!
I have electrical service in my garage but no outlet is connected to this box.
I opened up the box and there is three thick stranded wires. 1 RED, 1 WHITE, and 1 YELLOW, I think they are 10 gauge. The wires are too thick to connect to the outlet. My solution is to pigtail 14 gauge stranded wire to them using the Hot side to the Red and Neutral Side to the White using the line connections of GFCI. The Yellow Cable I left with a nut on it and is not being used. My circuit breaker for this line is at 15 amps. Is this safe or should I use thicker wires to pigtail? Thank you for your help!