Steps to turn on pump mode, perform a block text, and sample.

1. Press the center button to display the Main menu.
2. Select Modes > Leak check.
3. Perform a block test, following the on-screen instructions and prompts.
   CAUTION: Perform a block test in a known clean environment where gas alerts are not triggered.
4. Once the Leak check is successfully completed, select Pump run mode.