Book excerpt: Air conditioning in vintage cars often falls into disrepair, as owners figure that it never really worked all that well when it was new, and assume that rejuvenation would be prohibitively expensive. In his new book, Just Needs a Recharge: The Hack Mechanic Guide to Vintage Air Conditioning, Rob Siegel details exactly what's needed to resurrect long-dead air conditioning in a vintage car, or install a/c in a car that never had it. In a level of detail not found in any other automotive a/c book, Rob reveals what you need to know about flare and o-ring fittings, upgrading to a rotary-style compressor and a parallel-flow condenser, making or specifying custom hoses, and selecting refrigerant so that the a/c blows cold enough to be usable. Although the book draws from Rob's BMW experience (with specifics for the BMW 2002 and 3.0CS), and concentrates on vintage a/c systems (those that have flare fittings and originally contained R12), most of the information applies to any air conditioning system, foreign or domestic, vintage or modern. Written in Rob's entertaining Hack Mechanic narrative voice, and including 240 photographs and illustrations, the book covers theory, the choice of refrigerant (R12, R134a, other EPA-approved, non-EPA-approved), legality, tools for a/c work, fittings and sizes, the compressor, the evaporator assembly and expansion valve or orifice tube, the condenser and fan, the receiver/drier or accumulator, electrical connections and compressor cycling, connecting and using manifold gauges, the basic steps for a/c rejuvenation, from-scratch a/c retrofit, making and installing hoses, flushing the system, pressure-testing and leak detection, evacuating and charging the system troubleshooting, and other things that heat up the cabin.