Delta Controls HTP Installation, Operation And Maintenance Manual page 12

11. Install instrument conduit, wiring and purge gas tubing as
described below.
After installation and before reactor startup, perform
the Purge / Element Well Integrity Test on page 17.
This will verify that the element well was not broken
during installation, and that there are no problems with
the purge connections.
Performing this test as soon as possible prior to
reactor startup will allow time to obtain replacements
in the event of element well breakage. In general,
replacement is not possible while the reactor is
running. A thermocouple that has a broken element
well or that is improperly purged will only operate for a
short time before failing.
Page 12