Vaisala HMT140 - Manual (Page 54)

Replacing the HUMICAP® RH Sensor
46 VAISALA
Replacing the HUMICAP® RH Sensor
Replace a dirty filter to ensure maximum operating life and a
fast sensor response time. Do not attempt to clean the filter.
Fixed and Remote Probe Models
To replace the RH sensor:
1
Remove the filter (plastic grid or sintered stainless steel).
2 Remove the damaged sensor and insert a new one.
3 If required, recalibrate the probe (see Calibration and
Adjustment on page 48).
Removing and Fastening the Probe
Fixed Probe Model
To remove and replace a fixed probe:
1
Loosen the metal locking bushing by carefully turning it
counter clockwise.
2 Remove the probe from the transmitter by pulling it
gently outwards.
3 Attach the new probe to the 4-pin M8 panel connector at
the transmitter (only one position possible).
4 Tighten the locking bushing to the M8 panel connector
by turning it clockwise.