You ask about a book - is this because the Bentley and Haynes are inadequate? I haven't read them regarding a/c, so they may indeed be not enough. Telling what to do is not the same, IMHO, as telling why to do it.

All a/c systems are heat pumps. They absorb heat at point A and dissipate it at point B. A radiator is a heat exchanger, so also is the a/c condenser and a/c evaporator.

Freon-based a/c systems work on the ability of an expanding gas to absorb a lot of heat in the process of expanding. Even better, changing from a liquid to a gas absorbs even more heat. So a refrigerant that changes from liquid to gas under pressures and temperatures available in a car, or a house, or a refrigerator, makes the system possible. R12 and R22 have worked well for decades. Other substances work, too.

So start with the evaporator, in the car. It's a heat exchanger, absorbing heat out of the cabin air. The Freon is a low pressure gas in it. The vacuum created by the compressor sucks that out of the evaporator and raises it to a high pressure. The Freon gives up some of its heat just because of the compression.

The compressor sends the high pressure gas over to the condenser. The airflow though the condensor removes enough heat from the Freon that it converts into a liquid. That's why the sight glass, on cars that had them, show bubbles.

The receiver/drier/accumulator smooths out the pulses from the compressor and also removes moisture, and sends the high pressure liquid Freon over to the expansion valve, or variable orifice valve, which is at or near the entrance to the evaporator.

The high pressure liquid, forced though a small hole, looses pressure and converts back into a gas. Absorbs a lot of heat from the cabin air passing though the evaporator - another heat exchanger. And, we are back around the closed loop again.

End of lesson.

Condenser is the the high pressure side of the system. Replacing it is, as you surmised, a medium to large DIY job. Requires some special tools, namely a vacuum pump and maybe some refrigeration wrenches. Supplies like new 0-rings, and compressor oil, and parts like a new receiver/drier.

Keep the system sealed as well as you can. Slap a piece of duct tape over any open line while you are assembling the various parts. After installing everything, the condensor, receiver/drier, and anything else you decide to put in, and their 0-rings, evacuate the system and let the vacuum stay. It must hold, or else there's a leak. Only when there are no leaks should new refrigerant be installed. Use a little compressor oil on the 0-rings when installing.

This post has gotten alltogether too long.

I hope it makes sense and is helpful to you.

Good Luck,

Bob

:>)


PS Webster Groves HS '54