The air flow is controlled by using the toggle switch on the touchscreen.
Toggle to the right to turn the air on and toggle to the left to turn the air off.
The toggle displays blue to show that the air on option has been selected.
The air flow will not start until the test has begun, which is why the display window still shows as off.
Once the test has started, the air flow comes on and the display window will change to ON.
For diagrams and images, please download the PDF document.