Question
What can be done if there is a problem with flow through the Lachat PDS200 dilutor?
Summary
Issue with flow through dilutor.
Answer
If there is a problem with flow through the PDS200 Precision Dilutor System (Product # A89103/A89203) there are a couple of things that can be considered prior to shipping in for service.
- The ferrules can be replaced. If the ferrules are not forming a good seal, air will get pulled through and there may be little or no flow of the sample. If new ferrules are needed, one can order the NUT, 1/4-28 POLY - 1/16 (Product # 29005) and the Ferrule, 1/16 (Product # 29006); these both come in packages of two.
- The ports on the three-way valve can be flushed out. If there was particulate in a sample or sampler rinse station, the first narrow point it will reach is the three-way valve. To flush this out one can try the following:
- Disconnect the dilutor from the system. To do this remove:
- All tubing from ports of the three-way valve
- The diluent line and probe line from the front of the dilutor
- The sampler connection cable
- The power supply
- Hold the dilutor with the three-way valve pointing down over a sink or tub
- Rinse each of the three ports
- Press the brown button on the three-way valve to manually actuate the valve a few times while flushing each port. The button may be very stiff and not feel like it moves but it may still be actuating.
- Hook the dilutor back up and test it to see if the flow issue is resolved.
- Disconnect the dilutor from the system. To do this remove:
Below is an image showing the three-way valve.
