249W Level Sensor
Instruction Manual
Form 5729
March 2005
9
Figure 13. Blind Flange Installation
W8225
Handle the displacer with care.
Consider the characteristics of the
specific process liquid in use.
Check with your process or safety
engineer for any additional measures
that must be taken to protect against
process media.
Note
Except for gaskets (keys 12, 13),
trouble symptoms peculiar to specific
parts are discussed in the following
sections. Each section is specific to
these parts. Regardless of location,
gasket failure is indicated by leakage
in the gasket area. Every time a gasket
is removed, replace it with a new one
upon reassembly.
The procedures below apply to the Type 249W
assembly as shown in figure 16. Refer to figure 16
for key number locations.
Removing the Displacer and Stem
WARNING
Refer to the Maintenance WARNING at
the beginning of this section.
The displacer (key 4) is a sealed container. If the
displacer has been penetrated by process pressure
Figure 14. Type 249W Installation Complete
W8227
or liquid, it may hold pressure or hazardous liquid for
an extended period.
Process residue buildup on the displacer and stem
(key 11) may change displacer weight or
displacement. A bent stem or a dented or corroded
displacer can impair performance.
If the displacer rests against the travel stop, appears
to be overweight, or causes output drift or other
output inaccuracies, it may have been penetrated by
process pressure or liquid. Such a displacer may
contain pressure because it was in a pressurized
vessel, may contain process liquid that becomes
pressurized due to a change in temperature, and
may contain process liquid that is flammable or
hazardous.
WARNING
Sudden release of pressure, contact
with hazardous liquid, fire, or
explosion, which may result in
personal injury or property damage,
can occur if a displacer that is
retaining pressure or process liquid is
punctured, subjected to heat, or
repaired.
Handle the displacer with care.
Note
When removing the sensor from the
vessel or cage, the displacer may
remain attached to the displacer rod