Trolley Vacuum Troubleshoot

Vacuum assist helps increase filtration rate, but overzealous use can lead to problems. In our filter trolleys, vacuum is created by an AODD diaphragm pump. Our pumps create so much vacuum that a safety valve needs to be installed so the main trolley tube does not implode under pressure.

Though diaphragm pumps are made to operate dry and create suction, this situation decreases diaphragm life. If the vacuum is allowed to increase uncontrollably by revving the pump when a clog exists, the diaphragms tend to rupture. As vacuum increases, diaphragms blow up like a balloon in each stroke. Eventually, they are stretched so much that they rupture. If no solution is flowing to your pump, increasing pump speed should not be your first reaction to solve the problem.

The excess vacuum also creates other problems like torn paper or leaks through the gasket.

If you are having vacuum issues, always keep the pump at a slow pace. We recommend running the pump 25-40% power when running dry.

Here are some things to check:

1. Are your valves open? Sounds silly but this is a common error.
2. Is your filter cloth clogged? When was the last time you cleaned or replaced the cloth?
3. Is your filter paper clogged? Are you using the right grade of filter paper for the crude profile you are filtering? Is this a rough pass or a polish? Do you know the difference?
4. Are you using filter aides? If so, are you using too much, or the wrong kind?
5. Is your pump damaged? Perhaps your diaphragms are ruptured and that is why no solution flows.

To diagnose vacuum issues, we suggest you run your pump with room temperature solvent in a circular circuit, thus putting the pump discharge back into the trolley. Run without cloth or paper.

• Is the pump operating correctly? If so then there is no pump damage.
• Double-check that valves are open. Any change?
• Add filter cloth to the circuit. Does it operate normally?
  • Remember to always install filter cloth and always under filter paper.
• Add filter paper to the circuit. Are we still ok?
  • Never stack filter paper. It isn’t helpful.
• Add filter aide to the circuit. Notice any problems yet? If so, are you using the right quantity or type of filter aide?
• Evacuate all solvent and begin to filter your tincture. If problems occur, investigate the following:
  • Did the pump slow down after a while? Are you running too cold?
    • Running cold requires the use of a compressed air dryer.
  • Are you using the right paper for the filtration step you are on? Are your expectations exceeding the rapidity of the paper you are using? Familiarize yourself with the flow rate limitations based on paper grade.

99% of the time this solves al problems, but if you still have issues you should first read the user manual and the included SOP. If you need further help, please reach out and we can help.