Instruction manual

High Throughput Diffusion Pumps

DRAFT 12/23/04

Startup Procedure

To start the pump:

1. Evacuate the diffusion pump using a mechanical

roughing pump to below 0.5 Torr (0.67 mbar). The

diffusion pump will not function unless the discharge

pressure is less than the tolerable forepressure.

2. Turn on the cooling water supply to the pump

body and check that adequate flow is provided by

examining the amount of water discharged at the

visual drain points.

3. Switch on the power to the diffusion pump heater.

4. Check inlet and forepressure performance by means

of the system instrumentation.

Shutdown Procedure

To shut down the pump:

1. Close the inlet valve on the system, if equipped.

2. Turn off the power to the heaters.

3. For pumps equipped with the optional Quick Cool

Coil, admit water into the coil.

4. Continue to flow cooling water through the pump

(and Quick Cool Coil, if equipped) for at least the

time period listed under “Cooldown Time Without

Quick Cool With Quick Cool” in Table 4 on page 7.

5. Once the pump is cooled, shut off the mechanical

backing pump.

6. Air release the pump.

7. Continue cooling water flow until the pump is at

room temperature, then shut off the water supply.

CAUTION To prevent harmful collection of

condensate on the boiler plate, heater,

and heater terminals, do not operate the

Quick Cool coil when the pump is cold

or out of service.

WARNING 1. Releasing or admitting air to a

pump with a hot boiler, especially

when it is under vacuum, permits a

strong oxidizer to contact the hot

pump fluid and greatly increases

the risk of an explosion.

2. Boiler temperatures reach 530° F

(275 °C) which can cause serious

burns. Always check that surfaces

have cooled to near room tempera-

ture before touching them.