Advanced Instruments 3900, Service Manual

Page: 106 / 184

4CP189 Rev2
(4C35/3905 Service Manual)
Page 2 of 2
b. Gently pull the pump and its wires and
tubes out from under the instrument’s
cassette deck.
6. Disconnect the hose fittings (D), one at a
time, from the pump.
7. Disconnect the electrical terminals (E) from
the top of the pump.
8. Cut off any quick-disconnect electrical
terminals unplugged from the top of the
pump.
9. Strip about 1/2” off ends of the pump wires.
10. Making sure that the red wire goes to the (+)
terminal and the two black wires to the (-)
terminal, either:
• Crimp the smaller quick-disconnect
electrical terminals (supplied in kit) onto
the pump wires and connect them to the
two terminals on the replacement pump,
-- or
• Solder the wires directly to the replacement
pump terminals and insulate the soldered
terminals using insulation tape (not
supplied).
11. Place the replacement pump assembly in
correct position, with its terminals and tubing
to the right side.
12. Plug the outgoing hose to the top pump
fitting (F). The outgoing hose leads to the
sample cooling well.
13. Plug the incoming (heat transfer fluid) hose
to the bottom pump fitting (G). The incoming
hose leads toward the heat transfer fluid tank.
14. To perform a quick check that the pump is
functioning, reconnect the power cord and
turn on the instrument.
CAUTION: During this check, be
extremely careful to avoid contact
with the electrical components inside
the instrument.
The instrument will recognize that the heat
transfer fluid has been removed and prompt
G
F
you to add fluid. Add heat transfer fluid, as
described in your instrument’s User Guide.
15. After adding fluid, use the reservoir pump
push-button on the back of the instrument to
ensure that the pump is working properly.
You should hear the pump working. If the
pump is not working, recheck your
connections. If this does not solve your
problem, contact Advanced Instruments Hot-
Line Service.
CAUTION: Before resuming these
replacement instructions, turn off the
power and unplug the instrument.
16. Using cable ties (supplied in kit), secure each
pump hose to its respective pump hose
fitting. Be sure to check for leaks in and
around the tubing before securing.
17. Reposition refrigeration tape to cover all
exposed pump hose, fittings and tubing. Use
refrigeration tape (supplied in kit), if needed.
18. Using hardware supplied in the kit, attach the
pump assembly to the instrument.
19. Replace the instrument bottom front panel by
reversing steps 3-4.
20. Plug in the instrument and turn on the power.
The instrument will run a self-diagnostics
program.
21. Run a few test samples of calibration
standards to check proper instrument
operation.