Vaisala DRYCAP DMT143 - Maintenance; Periodic Maintenance

8. Maintenance
8.1 Periodic Maintenance
8.1.1 Cleaning
You can clean the body of the transmitter by wiping with a moistened lint-free cloth. Do not
immerse the transmitter in liquid, and do not use cleaning agents or solvents.
8.1.2 Calibration
DMT143 is fully calibrated as shipped from the factory. The recommended calibration interval is
2 years. If there is a reason to believe that the device is not within the accuracy specifications,
you can perform a field check using the DM70 handheld dew point meter.
If the field check indicates that the DMT143 is not within its accuracy specifications, contact a
Vaisala Service Center or your local Vaisala representative to have the DMT143 adjusted.
8.1.3 Changing the Filter
Replace the filter if it is contaminated. New filters are available from Vaisala.
Be careful when changing the filter, since it is easy to break the
sensor when the filter is removed.
CAUTION!
If the transmitter has the optional stainless steel filter HM47453SP
for vacuum applications installed, note that it has tapered threads and is not
meant to be removed on site. Trying to forcefully loosen the filter may damage
the transmitter instead. The filter replacement instructions below are for the
standard sintered filter DRW010335SP with parallel threads.
CAUTION!
If the transmitter is installed in a pressurized chamber, always make
sure that the pressure of the chamber is equalized with the ambient pressure
prior to removing the transmitter. When the transmitter is removed for
maintenance, cap the hole with a capped nut. This way, the chamber can be
pressurized although the transmitter is not in place.
Plugs are available from Vaisala for ISO and NPT threaded connections.
CAUTION!
When replacing the filter, wear clean gloves to avoid depositing dirt or oil on the filter. Inspect
the sealing ring for damage (used with ISO thread only), and replace it if necessary.
DMT143 User Guide M211435EN-J
62