You use electricity to charge your devices and to keep your home comfortable. That’s why it’s frustrating when the electricity does not work as expected. If the lights flicker after the HVAC starts up, it can cause a homeowner some stress. Does dimming or flickering lights when an A/C cycles on indicate a major electrical problem? It varies. When your HVAC unit starts, you may notice a slight dimming that lasts a fraction of a second. Your home has a regulated amount of electricity available at a time. You need a lot of electricity to cycle up larger appliances like your HVAC system. Those appliances also use more electricity when they are on. Your other appliances in your home, like your waffle maker, will not use that much power. If flickering is the only issue, your lights should only dim for less than a second and then quickly return to full brightness. Regular flickering lights may indicate a more extreme problem. Don’t investigate yourself because that can be extremely dangerous. If your lights continue to flicker, dim significantly, or trip the circuit breaker, contact a licensed electrician immediately. When there is not enough power to support all appliances, there will be normal flickering. However, a wiring issue could be the cause of constant flickering lights when you turn on your HVAC unit. The effect of the dimming lights is enough to make you notice a small or brief change. There may be something wrong with the outdoor compressor on your A/C if your lights quickly dim. Your home’s electrical system depends on circuit breakers. So, when the breaker trips and shuts off power, it means they are protecting you from a serious problem with your circuit.