I was doing some cleaning in the basement this afternoon and noticed I was getting pretty warm. Much later, during dinner, I checked the thermostat. It was set for 72 degrees (which is what we have to keep it at for the upstairs to be habitable), but the actual temperature was 78 degrees. I checked and made sure the fan was running, then asked jeff_duntemann to take a look at the compressor. He reported that it was blowing out lukewarm air and that there was ice. Ice is bad.
I called the business number for daisy_knotwise's former co-worker's husband, Lenny, who has a heating / cooling repair business and does our maintenance. After a few questions, he suggested that the filters in the air cleaner might be clogged. I'd looked at it, but Gretchen usually handles the filter cleaning -- and always has since the new air cleaner was installed -- so I'd not actually managed to pull the prefilters to look at them.
They were, in a word, grotty. Lenny suggested that we clean out the filters and the prefilters with a garden hose and put them back in the system to dry. In the meantime, we should crank up the heat for 10-15 minutes to thaw out the air conditioning system. And have towels ready in the basement for the water that was about to show up.
Fortunately, the water flowed toward the drain instead of the new carpet.
The air conditioning is back on now. I think it's working ok, but we'll know more in a couple of hours.
And I'm just happy I was dealing with Lenny, not Hubert Grimsley.