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AC Coolant Lines - Routing diagram

05-25-2010, 08:49 PM
I'm planning on refilling the freon (r134a) on my 98 Windstar with the type that includes a dye. However, there are multiple lines that also pass to and from from the rear AC.

Is there a diagram available that shows the entire coolant path? Haynes manual doesn't have it.



05-26-2010, 07:56 AM
I don't think the Ford service manual that I have even has a full schematic for the A/C, including the rear evaporator. However I believe I can accurately describe it in words.

From the pump, high pressure (& hot) vapor flows into the condensor. From the condensor, the high pressure liquid flows through the high pressure liquid line, which contains a split and two outlets, one for the front evaporator, one for the back. The front path first passes through the expansion orface, then through the front evaporator, while the back travels through a high pressure liquid line then the rear evaporator which contains a thermostatic expansion valve, and returns to the front. The two paths are combined at the accumulator/dryer. The accumlator has a pressure sensor that cuts off the A/C compressor if the pressure is too low (when refrigerant is lost to a leak) or too high (when pressure builds up due to low cooling demand). After passing through the accumlator, the vapor passes through a hose containing a muffler, then into the compressor.

06-04-2010, 07:25 PM

Thanks for the details.I'm also curious about the physical routing, but if they don't have a diagram for the system, I doubt they'll have illustrations. This is going to make tracing leaks a challenge.

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