The method
Before using the result
- Supply the correct saturation temperature for the measured refrigerant pressure. For blends, use the appropriate dew/bubble reference. No pressure–temperature database is assumed.
Worked examples
These original training examples illustrate the method for RETA CARO (Certified Assistant Refrigeration Operator). Use the matching “Load example” button above to explore a variation; example values are not equipment settings or prescribed criteria.
1. Worked example
Separate suction-line superheat from liquid-line subcooling. Supply the appropriate refrigerant saturation reference instead of interpreting gauge pressure as temperature.
- Calculation
- Superheat
- Measured line temperature
- 12 °C
- Supplied saturation temperature
- 5 °C
- Superheat uses line 12 °C and saturation 5 °C.
- Signed difference = 7 K.
- Superheat: 7 K
2. Comparison example
Compare a different supplied condition using the same method. For Technical Conquer, the important check is that the input meaning, units and method assumptions still match the problem.
- Calculation
- Subcooling
- Measured line temperature
- 35 °C
- Supplied saturation temperature
- 42 °C
- Subcooling uses line 35 °C and saturation 42 °C.
- Signed difference = 7 K.
- Subcooling: 7 K
Check your understanding
1. Which relationship is used?
Superheat = line − saturation; subcooling = saturation − line.
2. Which assumption should you check first?
Supply the correct saturation temperature for the measured refrigerant pressure. For blends, use the appropriate dew/bubble reference. No pressure–temperature database is assumed.
3. How should you verify a different unit system?
Convert every input to the displayed calculation units first. Equivalent physical inputs must give equivalent results; a unit label alone does not convert a number.
Continue with the matching exam topic
This tool connects to RETA CARO (Certified Assistant Refrigeration Operator) free practice. Work through a question independently, then use the calculation steps to identify where your method differs. The tool stays free whether or not you choose paid preparation.