Air Conditioner Repair
I could almost swear that in an early version of the RepairFAQ (about 8 years ago) there was a sizeable FAQ on repair and troubleshooting of air conditioners. Such an FAQ is nowhere to be found on the current RepairFAQ site. Have eight years of time fogged up my memory, or did Sam G. pull that FAQ for some reason? Anyway, here is the problem I was hoping to get some advice on. I recently picked up an old air conditioner in someones trash (I don't have the money to buy a new one). I thought maybe I could tinker with it and get it going. When I got it home and plugged it in, the fan worked great but as soon as power was applied to the compressor motor (turn up the COOL setting), the lights would dim WAY down and I'd have to turn it off immediately (otherwise a circuit breaker would blow). Once inside the unit (where I found the mfr date of Oct. 1975!), I disconnected the fan motor so I could hear what was going on in the compressor. Sure enough, it would just hum and dim the lights. At this point I figured it was shorted and that the unit was junk, but for some reason I kept cycling the power on and off to see what would happen. After several tries, the compressor loudly roared to life and the shop lights were no longer dimming. It was obvious from the noise, that the compressor has a very hard time starting up (seizing?). And it appears that the unit is sealed, so there's no way to service it (also, I don't want to fool around with the freon). My plan of action for now is to install a separate switch for the fan, so I can leave it off and listen for the compressor to start. Obviously this would be a bit of a nuisance, but it's still preferable to sweating my brains out in the 40oC summer heat! Anything else I can try, or is this the best I can hope for?
Answer:
You are right about the system being sealed and not home-serviceable. Since the compressor sounds normal (no clunking) and it does cool one can assume that the problem lies elsewhere. Look at the switch relay attached to the compressor canister. Try cleaning that first. The next step may be to replace that relay. If not bypass the relay and switch it on and off manually as suggested by yourself. Also clean all the insides of the a/c cabinetry, Your fan solution may work. Beyond that I don't suppose its worth spending anymore time or money on it. If you cut off the three tubes to the compressor (leave a few inches for a pressure regulator, etc.), you have an air brush silent air compressor that is worth a few hundred bucks (as prettied up by vendors) to hobbyists. You can probably ask for a hundred or so and all you have to do is to clean it up an give it a coat of paint. The law about releasing Freon applies only to businesses that deal with refrigerants. It does not apply to private individuals. If you are still concerned with the environment bring your a/c to a car aircon or some aircon business. They will be quite glad to remove that for you and resell the Freon for old equipment service calls. When salvaging the compressor always work with it in an upright position else the oil will leak out. Furthermore the compressor may pop out of its mounting springs and that's unrepairable.