Emerson Rosemount 228, Reference Manual, Page: 18 / 44

Retracting the Manual Retraction Assembly
Prerequisites
Make certain that the system pressure is less than 35 psig (342 kPa [abs]).
Procedure
1. Push in on the sensor using the top of the junction box. Slowly loosen the collet nut.
WARNING!
HIGH PRESSURE
Reduce pressure to 0 psig. Do not loosen collet nut until pressure is 0 psig.
Failure to reduce pressure may cause a loose collet nut to disengage and cause injury to
personnel.
2. When the collet nut is loose enough, slowly ease the sensor back so that it clears the
ball valve. Close the valve to the process line.
3. Drain the retraction chamber contents using the 1/8 in. flush ports.
4. Loosen the 3 in. hex union nut. Removt the sensor and tube assembly.
5. Replace the 3 in. hex nut O-ring. Place the sensor and tube assembly back in the
retraction assembly. Tighten the 3 in. hex union nut. Verify that the 1/8 in. flush
ports are closed.
NOTICE
With the ball valve closed and the retraction chamber 1/8 in. flush ports open, some
residual process fluid may leak from the 3 in. hex union nut female ACME threads. This
leakage is normal and to be expected.
WARNING!
HIGH PRESSURE
Retraction chamber contents may be under pressure. Before opening the ball valve,
make sure that the process pressure is less than 35 psig (342 kPa [abs]).
Failure to reduce pressure may cause a loose collet nut to disengage and cause injury to
personnel.
6. Open the ball valve and check for leaks. Insert the sensor into the process. Tighten
the collet nut.
2.2.2 Mechanical Retraction Assembly (PN 23311-00)
Installing the Mechanical Retraction Assembly
1. Tighten the sensor cable through the tube into the junction box. Screw the sensor
into the tube. Hand-tighten the sensor an additional half turn once the gasket is
seated.
Install
12 Reference Manual