In an orifice tube air conditioning system, where is the orifice tube located?

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Multiple Choice

In an orifice tube air conditioning system, where is the orifice tube located?

The main concept here is where the metering device sits to control flow of high-pressure liquid before it enters the evaporator. In an orifice tube system, the refrigerant leaves the condenser as high-pressure liquid and passes through the receiver/drier, then through the small orifice. The restriction causes a pressure drop, turning some liquid into a cold, low-pressure mixture that goes into the evaporator to absorb heat. So the orifice tube is located in the high-pressure liquid line after the condenser and before the evaporator (typically after the receiver/drier). Placing it elsewhere would not properly meter the high-pressure liquid or enable the intended phase change in the evaporator.

The main concept here is where the metering device sits to control flow of high-pressure liquid before it enters the evaporator. In an orifice tube system, the refrigerant leaves the condenser as high-pressure liquid and passes through the receiver/drier, then through the small orifice. The restriction causes a pressure drop, turning some liquid into a cold, low-pressure mixture that goes into the evaporator to absorb heat. So the orifice tube is located in the high-pressure liquid line after the condenser and before the evaporator (typically after the receiver/drier). Placing it elsewhere would not properly meter the high-pressure liquid or enable the intended phase change in the evaporator.

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