I apologize off the bat as this post may get wordy. I am replacing an over-the-range microwave with a new one. The house originally had a regular range and an over-the-range convection oven. The convection oven was long ago replaced by an over-the-range microwave, but it appears that the original 220 wiring to the convection was also used for the microwave. Within the breaker box, the white/black wires on this circuit were dedicated to the microwave, and the red wire was left loose, hanging in a coil at the bottom with a tag that reads: This conductor is spare in the microwave oven recpt. However, and this is my concern/question, when I test the red wire, it has continuity. Can I install the new microwave using this same wiring configuration? Is the red wire creating a potential fire hazard? All replies are appreciated. Thank you in advance for your help!