a/c fan idles forever?
My 3-year old indoor Lennox a/c system works great. Temperature swing continues to be more than 20F. But in the last few days of high temps, it's started doing something I don't recognize. In between cooling cycles, when the compressor is off, there is a faint rushing/humming sound coming out of the air handler. Sounds as if the fan is running slowly. Constantly. There is a very small amount of air (ambient temperature) coming out of the vents, so that's probably indeed what's happening. Why is this? I hear this long after the compressor has cycled off. I would expect that when a cooling cycle is complete, and the heat exchanger has warmed back up, the fan would eventually shut off entirely. I can cycle power on the whole unit, and the idling fan comes right back on.