A recovery cylinder that is half full of recovered R-22 at room temperature will be pressurized to approximately what level?

When discussing the pressure of a recovery cylinder containing R-22, it is important to understand the relationship between temperature and pressure for refrigerants. R-22, like most refrigerants, is a gas when above its boiling point and a liquid when below it, with its pressure increasing as temperature rises.

At room temperature (around 70°F to 72°F or 21°C to 22°C), the pressure of R-22 will correlate with its saturation temperature. For R-22, the saturation pressure at that temperature is typically around 130 psig (pounds per square inch gauge). When you have a recovery cylinder that is half full of R-22, a significant portion of the refrigerant is in the liquid state, while some is vapor. As the volume of liquid takes up space in the cylinder, the pressure will reflect the vapor pressure of the remaining refrigerant at that temperature.

Therefore, when assessing a recovery cylinder that is half full at room temperature, the pressure being approximately 130 psig aligns well with the known saturation pressure of R-22 under those conditions. This understanding ensures proper handling and safe operation of recovery equipment, as letting the pressure fluctuate beyond safe limits can lead to equipment failures or safety hazards.