A fixed-orifice metering device is most commonly found in which type of system?

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Multiple Choice

A fixed-orifice metering device is most commonly found in which type of system?

Fixed-orifice metering devices provide a constant restriction to refrigerant flow into the evaporator, with no adjustment for changing cooling demand. This simple, reliable approach works best when the system operates near a single design point, which was common in older high-pressure systems. In those setups, the head pressure is high and the flow is not modulated to match varying loads, so a fixed orifice keeps the design straightforward and economical. Modern variable-capacity systems use metering devices that actively respond to load (like TXVs) to maintain proper evaporator superheat and efficient operation; a fixed orifice wouldn’t adapt to changing conditions, making it unsuitable for those systems. Non-refrigerant or low-pressure scenarios aren’t the typical context for fixed orifice usage either.

Fixed-orifice metering devices provide a constant restriction to refrigerant flow into the evaporator, with no adjustment for changing cooling demand. This simple, reliable approach works best when the system operates near a single design point, which was common in older high-pressure systems. In those setups, the head pressure is high and the flow is not modulated to match varying loads, so a fixed orifice keeps the design straightforward and economical. Modern variable-capacity systems use metering devices that actively respond to load (like TXVs) to maintain proper evaporator superheat and efficient operation; a fixed orifice wouldn’t adapt to changing conditions, making it unsuitable for those systems. Non-refrigerant or low-pressure scenarios aren’t the typical context for fixed orifice usage either.

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