A:Answer Hi dcon. We regret to read that your LG 2.0 cu.ft. Over-the-Range Microwave Oven, Model # LMV2031 is not heating at all. It could be that you have a defective magnetron, a defective diode or a defective high voltage capacitor. If the diode in your microwave becomes defective, your microwave will not heat and you will hear a buzzing or humming noise. A defective capacitor will also prevent the microwave from heating and will also cause the buzzing and humming noise. A defective magnetron is the third possible cause. The unit will need to be inspected to determine what the issue is and to give you an estimate for the cost of repair. You can contact our Support Representatives at (800) 243-0000 to get assistance setting up a repair service...^IFV