Tuttnauer 2540 EHS, Technician Manual

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9.16 The Vacuum Pump
9.16.1 Description
To produce the vacuum needed in the prevacuum and drying
stages, the autoclave is equipped with a liquid ring pump. This
pump is suitable for continuous operation, and achieving a
high vacuum necessary for proper operation. To produce the
needed vacuum the pump draws water from the reserve in the
rear compartment of the water reservoir. There is a minimum
Water Quality requirement for the pump to ensure trouble free
operation (ref. par. 3.8.2.)
A float switch is mounted to the lower rear wall of the
reservoir to prevent the pump from running when there is no
water in the reservoir.
9.16.2 Replacing the vacuum pump
Caution!
Before starting, disconnect the instrument from the power
source and ensure that there is no pressure in the
autoclave’s chamber and jacket.
For location of inlets and outlet of the pump, refer to
drawing on the next page
1. Take off the autoclave cover (see para. 9.2 “Removing
the Outer Covers of the Autoclave”).
2. Close the external Feed Water Supply valve going to the
back of the autoclave. Count the number of turns and
mark it down for use at the end of this procedure.
3. Drain the water from the reservoir, using the manual
drain on the front of the machine.
4. Disconnect the electrical wires from the pump. Note the
location of the wires for later use.
5. Disconnect any plumbing. Note the location of the
plumbing connections for later use.
6. Replace the pump.
7. Reconnect the wires and piping previously removed.
Caution
Ensure that the protective earth ground of the
vacuum pump is reconnected before power is turned
on.
8. Open the external Feed Water Supply valve going to the
back of the autoclave. Make sure to open it the same
number of turns as had been counted earlier. Allow the
rear compartment of the reservoir to fill.
9. Turn on the power and observe that the reservoir fills
properly. Run a sterilization cycle to verify that the pump
performs correctly, without leaking.
10. Reassemble the cover.