Waters ACQUITY QDa - 3.13 Gas Ballasting the Rotary Backing Pump; 3.14 Replacing the Rotary Backing Pumps Demister Element; Replacing the Internal, Source Exhaust Valve (KAD)

June 28, 2016, 715003956 Rev. C
Page 51
3.13 Gas ballasting the rotary backing pump
Note: This section applies to the Performance QDa Detector only. The Standard instrument uses a
diaphragm pump, which does not require oil.
For more information about gas ballasting the backing pump, see The VACUUBRAND Technology
for Vaccum Systems Instructions for Use (VACUUBRAND rotary vane pump: model RE 6, part
number 99139 / 11/20/2013).
3.14 Replacing the rotary backing pump’s demister element
Note: This section applies to the Performance QDa Detector only. The Standard instrument uses a
diaphragm pump, which does not require oil.
For information about replacing the backing pump’s demister element, see “Troubleshooting” in
the VACUUBRAND Technology for Vaccum Systems Instructions for Use (VACUUBRAND part
number 99139 / 11/20/2013).
For ordering parts, contact Waters (see page iv).
3.15 Replacing the internal, source exhaust valve (KAD)
Replace the source exhaust valve annually or when a source-pressure test fails and all other
causes of failure have been investigated.
Note: The following procedures apply only to instruments fitted with the internal, source exhaust
valve (serial number suffix "KAD"), shown in the figure below.
See page 19 for guidance on identifying your QDa version and page 86, for details about replacing
the external, source exhaust valve assembly (serial number suffix “KAB”).
Notice:
• To avoid damaging the pump by running it dry, and filling up the trap bottle and exhaust
lines with oil, do not leave the pump constantly in ballast mode.
• To prevent the pump failing to start, do not power-on the QDa Detector when the
backing pump is in ballasting mode.