I have seen some Escorts in salvage yards in Pennsylvania that didnt have a.c. on them. Temperatures of 100° in PA are rare.
Adding an a.c. is going to be a BIG job UNLESS it had one that wasnt re-installed; in fact if it never had one, it might be an easier task to get an Escort that has an air conditioner, and use your current one as a source of spare parts. If it did have one once, I expect it would be feasible to add the missing pieces.
Here are some of the things you would have to do:
* First spend time in Salvage yards scoping out whether it is feasible at all, whether yours had one once, and if so how much of the works are still in the car. I know on a Dodge Omni, if the car came without an a.c. the firewall is different, and wont have any place where you can make the opening for the a.c. piping. I dont know about Escorts.
Then, if it seems feasible, here are some of the steps:
* Add the evaporator under the dashboard. If I had to do this, I would get the entire heater/evaporator assembly from a salvage yard, with all control cables, and the control head (where you set the temperature and air flow). Then you would have to remove the dashboard, to have access for replacing the 'heater-only' unit in your Escort.
* Add the a.c. compressor. This would involve getting the correct engine accessory bracket from a salvage yard, along with the correct tensioner and idler pulleys for that bracket. Get the proper serpentine belt too. You would also need to make sure you had the proper connections (wiring harness and hoses) for the alternator and power steering units - since they may be in different positions on a car having a.c. versus one not having a.c. You would need the refrigerant hoses involved. Dont re-use old tensioner or idler pulleys; get new one with new bearings in them.
Since the wiring harness for the car would probably not have the wires for the a.c. (though it might have them hanging there anyway) you would have to wire up the circuits to turn on the a.c. compressor, along with the radiator fan, and include the high-pressure cutoff and low pressure cut-off sensors.
* Adding the condenser in front of the radiator would be one of the easy steps.
* If I were going to be doing this much work on an Escort, I would probably replace the timing belt, its tensioner pulley and the water pump while I had things partly dismantled. On mine the lower radiator hose connects to the water pump, inside the engine accessory bracket - and is miserable to reach unless you have removed the p.s. pump and alternator and a.c. hoses! Then you could forget about it for at least 60,000 miles.
Any work you do on your car, you should make a note of what was done, with the date and mileage. This will increase the price you get when you want to sell it, or just make it easier to keep up the maintenance.
If the car did have a.c. it may still have its evaporator under the dashboard. Then I would wonder if the openings in the tubes were capped off. If they werent you will be dealing with corrosion inside the evaporator, and will need to be a careful flushing and evacuation before recharging.
Even if you do move to another Escort having an a.c. already installed, be prepared to spend $$ to get that a.c. working again. A ten year old a.c. system will likely need a rebuilt compressor (or it will leak from the input shaft seal), and possibly new refrigerant hoses, as well as the new receiver/drier of course. My Escort is a 92, so its a.c. uses the old R-12 refrigerant, and doesnt work anymore. If I were going to fix it up, I would certainly convert to R-134. R-12 is too expensive, and the 'alternate' refrigerants are mostly illegal. And new refrigerant hoses would be a very good idea. R-134 operates at higher pressures than R-12.
You should spend time reading in the forums and the FAQ at
www.ackits.com. Its the closest thing I know of for guidance on working on the auto a.c. system.