Roche Diagnostics May 2009
B-42 Service Manual · Version 9.0
4 Components cobas b 221 system
ISE measuring chamber (cobas b 221<3>–<6> systems only)
2
Release the four hooks at the end of the fan protector.
3
Lever the head of the NTC cable out of the fan protector with a screwdriver and
slide the cable out.
4
Remove the fan protector.
Use the reverse order for assembly.
Replacing the electrode locking lever (BG module)
1
Remove the cobas b 221 system top cover, open the BG measuring chamber and
remove the electrodes.
2
Half open the electrode locking lever, hold it in place with both hands and pull it
up.
3
Disconnect the tube and remove the electrode locking lever.
Use the reverse order for assembly.
Replacing the center seal (BG module)
1
Remove the cobas b 221 system top cover and open the BG measuring chamber.
2
Open the electrode locking lever.
3
Remove the electrodes.
4
Remove the center seal (blue plastic ring on the right interior panel) with
tweezers.
Use the reverse order for assembly.
ISE measuring chamber (cobas b 221<3>–<6> systems only)
Replacing the ISE measuring chamber
1
Disassemble the sample distributor cartridge.
e
For instructions, see Replacing the sample distributor cartridge on page B-35.
2
Open the ISE measuring chamber, remove the electrodes and the electrode
locking lever and pull out the tube to the measuring chamber cartridge on the left
side.
3
Close measuring chamber and unscrew the three screws holding the ISE module.
e
For details, see Figure B-25 on page B-41.
4
Disconnect the tube adapter to the MSS output pump.
Do not use tools to install the new center seal, otherwise it may be damaged.