Section 34 (A/C-Heater System - Manual): Description
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All models except Nova, use a cycling clutch orifice tube (CCOT) to meter the flow of refrigerant into the evaporator. A pressure cycling (sensing) switch cycles the compressor on and off to maintain the desired cooling and to prevent evaporator freeze-up.
All models use a 4-cylinder radial, 5-cylinder (V5) or 6-cylinder axial compressor except Nova depending on engine and body style. On Nova, a Nippondenso 10-cylinder compressor is used.