HP Performance Optimized Datacenter 20c Maintenance And Service Manual page 63

Remove the two retaining screws, and then remove the humidity sensor housing from the wall (4).
5.
Replacing the humidity sensor
Re-attach the humidity sensor housing to the wall (1).
1.
Replace the two self-tapping screws (2).
2.
Reconnect the wires to the hot-aisle humidity sensor.
3.
Replace the sensor cover (3).
4.
Replace the four screws that secure the sensor cover (4).
5.
Removal and replacement procedures 63