Heating & A/C (A7)Question 85 of 120
The expansion valve or orifice tube controls:
a.Compressor speed
b.Blower motor voltage
c.The flow of refrigerant into the evaporator, causing a pressure drop
d.Cabin air recirculation
Explanation
The metering device drops the refrigerant pressure and controls flow into the evaporator, allowing it to boil and absorb heat. A restricted orifice or stuck valve causes poor cooling and abnormal pressures. It separates the high side from the low side of the system.
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