City & Guilds Level 2 Award in F-Gas Practice Exam

The calculation of the system compression ratio is determined by dividing the discharge pressure by the suction pressure, both measured in gauge pressure. The compression ratio is a key aspect of a refrigeration or air conditioning system as it indicates how much the refrigerant gas is compressed from its low-pressure state (suction) to its high-pressure state (discharge).

By using gauge pressure for both measurements, the calculation helps to focus on the effective pressures that the system operates under, excluding atmospheric pressure influences. This ratio is critical for assessing the efficiency and performance of a refrigeration system, enabling technicians to understand how much work the compressor is doing in terms of raising the pressure of the refrigerant.

Using this method provides a clear numerical representation of the compression that occurs within the system, allowing for better diagnostics and maintenance planning.