1. Remove the water tank cover and water tank from the machine.
2. Remove the top tray by removing the 6 screws shown here. It will lift off when all the screws are out.
3. Remove the inner top panel from the machine by removing the 2 7mm nuts holding it in place.
4. Adjust the flathead screw in the pressure stat to change pressure. Clockwise will increase boiler pressure, counterclockwise will decrease boiler pressure. Only make 1/2 turn adjustments at a time and allow the machine time to stabilize before further adjustment for safety reasons - too large of an adjustment may create too large of an increase in pressure which could damage the machine or cause injury.