1. Purpose of the OPV
The Over-Pressure Valve (OPV) is designed to regulate the maximum brewing pressure, thereby preventing over-extraction and protecting the machine from potential damage.
2. Recommended Pressure Setting
The ideal brew pressure range is 9–12 bar. Note that actual pressure can be influenced by factors such as grind size, coffee dose, puck density, and the overall extraction system.
3. Dual-Mode OPV Overview
The G3028A is equipped with a dual-mode OPV that supports both preset and manual pressure control, offering flexibility for users at all experience levels.
4. Tips for Beginners
Before adjusting the OPV, ensure your grind size is calibrated to reach approximately 9 bar under default settings.
Avoid lowering the pressure below 6 bar during extraction.
Keep in mind that while proper OPV settings help achieve extraction stability, final flavor is also affected by grind quality, coffee beans, and brewing technique.
For further guidance, please watch the "OPV User Guide" video tutorial:
https://www.youtube.com/watch?v=oU_J6_7VPBc