6. Faults / 7. Maintenance and cleaning
Faults
Not possible to
screw the instrument
EN
into the thermowell
Dial has become
coloured
Window cracked
7. Maintenance and cleaning
Personnel: Skilled personnel or service personnel
Tools: Suitable spanner
For contact details see chapter 1 "General information" or the
back page of the operating instructions.
7.1 Maintenance
These gas-actuated thermometers are maintenance-free!
The indicator should be checked once or twice every year. To do this,
the instrument must be disconnected from the process and checked
using a temperature calibrator.
Repairs must only be carried out by the manufacturer.
18
Causes
Incorrect thread or stem
diameter or thermowell
stem too long
Ambient temperature
too high
If necessary, secure
thermometer via the
case
WIKA operating instructions models 73, 74, 75
Measures
Exchange thermometer or
thermowell
Isolate against radiated heat
Exchange the instrument