From charging your electronic devices to keeping the inside temperature comfortable, your home runs on electricity. That’s why it’s very frustrating when electricity does not work as expected. If the lights flicker after the A/C or furnace starts, it can cause stress to the homeowner. Does dimming or flickering lights at the start of HVAC cycles reveal a dire electrical problem? It depends. When your HVAC starts, you may notice a dimming that lasts for less than a second. Your home has a regulated amount of electricity it can use at any given time. And large appliances like your HVAC system need a lot of electricity to start up. Those appliances use a lot more electricity when they are on. Your smaller appliances in your home, like your toaster, will not use as much power. If this is the only issue, then your lights should dim for a second and then quickly return to full brightness. Flickering lights may reveal a more serious problem. Don’t investigate yourself because it could be dangerous. If your lights continue to flicker or dim significantly or trip the circuit breaker, contact a professional immediately. When there isn’t enough power for all the appliances in your home, there will be normal flickering, but a wiring issue might be the cause of flickering lights when you start your HVAC system. The impact of dimming is enough to make you notice a small or quick change. There may be something wrong with the condenser or your A/C if your lights suddenly dim. Your home’s electrical system relies on circuit breakers. So, when they trip and then shut off power to a part of your home, they are protecting you from an issue with your circuit.