COMPRESSOR CLUTCH CONTROL
Evaporator Temperature Switch
Although compressor clutch does not normally cycle on and off, an evaporator temperature switch turns off the compressor clutch if evaporator temperature decreases to 32øF (0øC). This prevents evaporator icing.
A/C Pressure Switch
A/C pressure switch is a triple-pressure switch, which monitors high side pressure. See Fig. 1. If pressure decreases to less than 17.4 psi (1.2 kg/cmý), A/C pressure switch interrupts power to compressor clutch (low-pressure cutout). Switch closes when pressure increases to more than 34.8 psi (2.4 kg/cmý).
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