I've been having a seriously nice summer so far... it started two or three days ago, didn't it? I missed seeing the announcements on the TV, or on Google, that accompany each solstice and equinox. I'm sure there must have been such announcements for the beginning of Summer 2017 but I obviously wasn't paying attention.
A few days ago my central heat and air went out. "A few", in this case, means 160, because it was the middle of January when it stopped working. Do I know the ins and outs of my system?... no, but I know the fan that pushes the air was what stopped working. The thing I didn't know was whether there is more than one fan. An intensive 2-minute examination of the system, which is a heat pump system, took me less than 3 months to complete. I came to the possibly correct conclusion that the fan in the outdoor unit of the system is the one and only fan.
Whenever I attempt to turn on the heat, the a/c or "fan only" with the switches on the thermostat, there is a buzz like the fan wants to start, but it doesn't. Meanwhile, I got through the cold months with a couple of electric portable heaters. I got the first one from Lowes and the second one from major river in South America called Amazon.
It was definitely better to not use the central heat anyway, because there was a critter or critters wintering under my floor. Squirrels or a cat, I think. I thought it or they had actually chewed into the heating ducts, because I would hear them clawing, running, and scratching very loudly right next to the floor vents, and almost every night I was sure I'd catch sight of the intruder by peering down through the louvered vent grate openings in the bathroom, bedroom and living room. Now, though, since I've never spotted the varmint, I'm thinking it made entry holes in the plastic sheathing and is living in the nice, thick fluffy insulation.
End of Installment One... writing is hard! Installment Two will be here after I'm sufficiently rejuvenated.
There are probably 2 fans, 1 for the outdoor condenser unit and one for the furnace/ air handler. Does the outdoor fan just hum?, if so take a stick and turn it in the direction that would blow air upwards out of the unit and see if it will start up (Thermostat needs to be on Cool and Fan on Auto for this). If it does start up then you may just need a $30 fan "run" capacitor.