How to fix the insulation on burned wire quickly and easily Fix burned wire inside electrical boxes by replacing charred insulation. A junction box is an important feature of an electrical system as it serves the different connections towards achieving the goal of a proper electrical distribution without leading to short circuits. So you're finally getting around to replacing the ceiling light fixture when you discover that the. In this video, an experienced electrician shares his tips for repairing a junction box and connects a copper conductor to an aluminium one. After the repair, I tested how the wires heat up under real load. This sensory clue means that conductor insulation is overheating, creating a dangerous situation and an immediate fire hazard. In this blog post, I will share several effective methods for how to fix burnt electrical wires that have become compromised through burning or melting so you can safely resolve the issue and rest easy knowing your home's electrical system is back in good working order.