What can a pressure reading along with a temperature reading indicate in a refrigerant recovery cylinder?

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Multiple Choice

What can a pressure reading along with a temperature reading indicate in a refrigerant recovery cylinder?

When you have a pressure reading paired with a temperature reading in a refrigerant recovery cylinder, you can compare the measured pressure to the expected saturated-vapor pressure of the refrigerant at that temperature. If the pressure is higher than what the refrigerant’s saturated pressure would be at that temperature, it points to non-condensables (like air) in the cylinder. Those gases don’t condense and raise the overall pressure for a given temperature, so the P–T mismatch indicates excessive air or non-condensables. The other possibilities don’t fit this specific scenario as neatly. A leak would more commonly show a pressure drop over time rather than a single elevated pressure for a given temperature. Degraded refrigerant and being full of liquid don’t produce the same telltale-pressure-with-temperature mismatch.

When you have a pressure reading paired with a temperature reading in a refrigerant recovery cylinder, you can compare the measured pressure to the expected saturated-vapor pressure of the refrigerant at that temperature. If the pressure is higher than what the refrigerant’s saturated pressure would be at that temperature, it points to non-condensables (like air) in the cylinder. Those gases don’t condense and raise the overall pressure for a given temperature, so the P–T mismatch indicates excessive air or non-condensables.

The other possibilities don’t fit this specific scenario as neatly. A leak would more commonly show a pressure drop over time rather than a single elevated pressure for a given temperature. Degraded refrigerant and being full of liquid don’t produce the same telltale-pressure-with-temperature mismatch.

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