Brooks Instrument Mfi Series - Manual (Page 46)

4-8
Brooks ® Mf Series
Section 4 Maintenance &
Troubleshooting
Installation and Operation Manual
X-TMF-Mfi-Mfx-MFC-eng
Part Number: 541B074AAG
August, 2009
4. Carefully remove the valve stem assembly (24).
5. Remove the plunger assembly (26, 29, 28B and 32).
6. Remove and note the position of the valve spring spacers (28A) which
may be located above and/or below the lower valve springs (29).
7. Unscrew the orifice (33) from the flow controller body.
8. Carefully unscrew the valve seat (32) from the plunger (26). Note the
position and number of spacers (25A) and springs (29) that are stacked
on the threaded end of the valve seat.
9. Remove the cover from the electronics housing by loosing the four (2)
self retained screws in the corner of the cover.
10.Unplug signal wire terminal strip connectors TB-1 and TB-2.
11.Loosen the four screws (4) in the corner of the housing using a long
(6 inch) 3 mm hex wrench. Lift the housing off the circuit board. Note:
Signal wire assembly is still installed through housing gland or conduit
fitting(5).
Be careful not to stress the sensor flex circuit cable when
removing the sensor connector from the PC Board. If the sensor
cable is stressed, an open in the sensor wire could result.
CAUTION
12.Unplug the sensor connector from the PC Board. Remove the screw
and washer (42 and 43) securing the PC Board ground lug. Remove
the two screws (17) and washers (16) securing the PC board (14).
Remove the PC board.
13.Remove the two screws (37) and washers (38) securing the sensor
assembly (18). Remove the sensor assembly. (Mfi Series only)
Note: Do not attempt to disassemble the sensor assembly.
14.Remove (Mfi Series only) sensor assembly O-rings (25B) from the flow
controller body. Using the Brooks O-ring removal tool will help prevent
scratching the sealing surface (Refer to Section 5, Table 5-5).
15.For Mf50/60, remove the adapter fittings from the flow controller body.
16.For Mf50/60, remove the restrictor assembly (40) from the inlet side of
the flow controller body using the restrictor tool (part of service tool kit
listed in Section 5, Table 5-5).