It's probably too cold. Remove the front louvered cover to expose the cap tube. The one from the stat. remove the rubber bumper from the front coil and pull the cap tube from the rubber. Hold the cap tube in your hand until you feel that the tube is pretty warm. then turn the unit on. How long does it run ? If the stat is a snap action one find yourself a portable heater with a fan, an old car warmer will do. Have it pointed to the area of the stat. Let it get good and warm. How long does it run ?

The tech came out and it's back up and running for now... He put a hard start on it. The unit froze up 3 weeks ago and they charged it. Today, he said that it's pretty low on freon again, and showed me the leak in the coil. Looks like we're going to have to replace the unit as they can't repair the leak, because it's too big. There's an oil slick on the side of the fins.

Update: After running for 8 days w/o the condenser fan, I hear it no more, so I think the compressor finally locked up. It was sounding really ragged near the end, kinda like a small engine running with no oil. Whereas I would never intentionally destroy anyone else's property, having that old earsore of an air conditioner finally bite the dust through someone else's negligence isn't going to make me shed any tears. In any case, there was a huge yellowjacket's nest inside that electrical disconnect box, and I wasn't going anywhere near it, I'm allergic to wasps. Dave

Thanks to Dovetonsils for the lead on the contactor (in my non-HVAC-speak, this would be called a relay). After a little web-searching Friday based on his\hersuggestion, I was able to pinpoint the contactor as the likely source of the problem and yesterday I put another one in. All is peachy now! For others with the same problem, I pulled the thermostat unit off the wall mount pins but the condensing unit continued to run, so I knew it had to be something with the circuit board on the air handler or the condensing unit itself. I then turned off the power to the air handler\circuit board, but the unit continued to run. At that point, it almost certainly had to be an internal wiring issue with the condensing unit. After making sure the circuit breakers were turned off to both the air handler and the condensing unit, I pulled the quick disconnect (what I call the wall-mounted fuse cartridge). I then unscrewed the panel on the unit. I saw the two silver capacitors that looked like whiskey flasks, and with a couple of insulated screwdrivers I shorted out the contacts on each. No sparks were noticed, but I had read that the wiring in the fan motor would have essentially discharged the capacitors soon after the power was turned off. Still, it never hurts to be careful, or put another way, it can sometimes hurt when you aren't careful. The contactor was obvious (I had seen a lot of pictures of it on the web by that point), and frankly a little disappointing in its simplicity. I took a bunch of photos of it with my phone from different angles, drew a diagram of it on paper indicating which wire went to what and how it was attached, and then labeled each of the wires with some tape ("upper left", lower right", etc.). Yes, this was overkill, but it was also new territory for me so I wanted to be sure to get everything back in the right order. I unscrewed the sheet metal screws holding the contactor to the internal sheet metal, then with it in my hand I pulled off or unscrewed the wires connected to it. I could now inspect the contactor, and could see that the contacts (like automotive distributor points) were both blackened and melted in places. The spring loaded plunger that raised and lowered the contacts seemed to be fine though (my assumption was that the plunger itself had some sort of problem, but that didn't seem to be the case). My guess was that the heat from arcing from the points to the copper plate might have caused the areas of contact to stick to each other. Whatever the problem, the contactor had to be replaced. I checked with all of my local hardware stores, appliance repair shops, and A\C distributors. Everyone was friendly and most had what I was looking for (a single pole contactor rated at 30 amps), but they all politely declined to sell me one, saying either that it wasn't an end user item ("not for the DIYer") or that they only sold to licensed contractors. I could see that these things are readily available on line and pretty standard in design. I was just about to order one when I happened to go out and get the mail. When I got to my mailbox I saw a truck owned by a friend of mine who has an apartment rental maintenance company. I explained what I was looking for and he said he had three on his truck. If I replaced it with a new one at some point, I could have one of his right now. Bingo. I hooked it up in a flash, remounted it on the sheet metal, closed up the panel to the condensing unit, and then began to turn the power back on to the air handler and the unit. I turned the thermostat to cool, and heard the lovely sound of both the fan and the condensing unit kicking in. When that side of my house got to the desired temp, the thermostat shut off, and miracles of miracles, the condensing unit did as well. Thanks to everyone else who provided advice. Unfortunately, I didn't see the answers until the morning, but all of the suggestions were sound one. Happy (and cool) Sunday to everyone! Nick in Palm Springs