Basically, the symptoms are these:
* From an off state, I turn on the thermostat to Cool and the compressor starts up. About 20-30 seconds later, the blower on the furnace comes on. The air's good and cold -- no problems so far.
* Anywhere from 10 to 30 seconds later, the compressor and fan click off and then immediately back on. It repeats this 4 or 5 times, speced anywhere from 5 - 30 seconds apart. After that, the compressor/fan shuts down.
* As soon as the compressor stops, the furnace's blower kicks into high gear. It is then impossible to stop the blower by means of the thermostat. Turn it off, turn up the temp, turn it to heat, remove it from the wal, ... the blower keeps going. To turn it off I have to use the switch in the furnace cabinet.
* Now, even though it's off, if I turn the switch in the furnace cabinet back on, the blower comes right back on (compressor/fan still off) and will run indefinitely (as far as I know -- I've let it go for an hour once before shutting it off again).
I end up having to wait anywhere from an hour to a day or more before I find I can turn the switch in the furnace cabinet back on and NOT have the blower start. At that point, I can restart the whole process: turn on the A/C and the compressor comes on, etc.
The two techs that cme out both diagnosed the problem as the compressor overamping. Here's their exact diagnoses:
Tech #1: "Unit is way overamping. Rated at 18.6 amps, amping at 19.8 amps. Overamping due to burned contact points and wrong size fuses."
Tech #2: "While out by condenser running, compressor dropped out. When it reset checked amp drain. Compressor is overamping, will need to replace."
The second tech said the burned contact points and fuse couldn't be the problem and that the entire compressor would have to be replaced. Based on other feedback I've received, the consensus seems to be that neither tech is correct.
Thanks for reading all of that, and thanks for any advice you can give me. I'm scheduling a third tech to come out but would like to have more of a clue before he starts so hopefully I can steer him in the right drection.
Thanks - Ken