LevelVent 5 loggers detect pressure. A vent tube to surface allows barometric effects (+B) on the pressure sensor to be eliminated (-B).
LevelVent 5 loggers provide readings (L) of the actual pressure of just water above the pressure sensor Zero Point.
The best recommendation is to compare LevelVent readings (L) with a manually measured depth to water level value (d) (using a Water Level Meter).
To adjust all readings in your LevelVent file to depth to water below a well casing (d), record a manual water level measurement using a water level meter. This reading should correspond in date and time with an actual LevelVent recording. Use this as a reference datum in the Manual Data Adjustment option in the Levelogger Software Data Wizard.