Operator’s Manual: Dura Dry II
Troubleshooting
© SP Industries, Inc.
Rev.004, 12/07
25
Vacuum Leak Troubleshooting Procedure
Should you determine that you have a vacuum leak in the Dura-Dry II MP Condenser Module we
suggest that you use the following procedure. This procedure should be done on the Dura-Dry II
MP Condenser Module alone. If a manifold system is connected to your
Dura-Dry II MP
Condenser Module you should disconnect it and replace the test plug in the 2.5 inch top port
(making certain that the black rubber grommet is round). If you have a Tray Dryer connected to
your Dura-Dry II MP you should locate a #13 rubber stopper and introduce it to the connecting
vacuum port in the Tray Dryer.
In order for the freeze-dryer to achieve maximum low pressure the system must be clean and dry
and the condenser temperature must reach its specified low. It will often be necessary for two
people to conduct the vacuum leak troubleshooting procedure. One person will need to
manipulate the system, and the other will need to watch for vacuum fluctuation at the appropriate
digital readout. Allow a 1-minute interval between each manipulation. This will allow the system to
respond to any changes you may have made.
1. Following the original manufacturer's instructions change the vacuum pump oil. Contamination in
your vacuum pump oil may decrease the optimum capacity of your pump.
2. Make sure that the drain hose is plugged.
3. Open the condenser door. Using two #2 rubber stoppers, plug the condenser outlet ports on the
condenser housing.
4. Activate the vacuum pump. Once a good vacuum is verified between the vacuum pump and the
condenser shell, turn the system
OFF
, remove stoppers, and close the condenser door.
5. Press
the
START/STOP
button. Allow the system to reach its maximum low pressure and
temperature.
6. Leak check the front end plate gasket and watch the vacuum indicator for pressure fluctuation.
Look to see if Snoop has entered the condenser.
7. Leak check the green epoxy fittings at the condenser outlet. Watch the vacuum indicator for
pressure fluctuation.
8. Leak check the back condenser end plate gasket, being careful to snoop only the gasket. Watch
the vacuum indicator for pressure fluctuation.
9. Carefully slice the black tubular insulation at the rear of the condenser end plate exposing the
green epoxy joints to the end plate and the compression fitting joint to the stainless steel
condenser coil.
10. Leak check both condenser end plate feed-throughs with Snoop. Watch the vacuum indicator for
any fluctuations.
11. Leak check with Snoop the thermocouple feed through assembly (20A). Watch the vacuum
indicator for pressure fluctuation.
12. As an additional check, you may wish to stopper the 1/2" port between the chamber (or manifold)
and condenser and check the vacuum.
At this point, if you have not found the source of the vacuum leak, contact the
FTS Service
Department.
