Last July, as the sun blazed down and turned my apartment into a sauna, I started noticing something off with my air conditioner. It was working—sort of—but the cool air felt more like a half-hearted breeze, and there was a faint buzzing sound I couldn’t ignore. With Summer still a few months off, I’ve had time to reflect on that sweaty ordeal. Here’s my story of figuring out the signs your air conditioner needs repair—hopefully, it’ll save you from a similar fate when the heat hits.