So last night around 7:00 pm, two weeks before a new furnace is going to be installed, the 20 YO one quits. The condensate pump had been misbehaving, primarily because it was filled with gunk, and I’d tried to rinse it out, but finally gave out and took it apart and really cleaned it out. Anyway, the furnace stopped igniting around the same time. It would turn on the fan, increase the fan speed, and then slow down the fan again. No heat. I called my power companies home warranty line around 9:30, and a repair guy arrived around an hour or so later. After a considerable amount of time, a diagnosis was achieved, and off he went to retrieve a new part. An hour or so later, the part was installed, and the furnace started running again.