Deep Clean Your Freeze Dryer's Industrial Pump

If you notice that drained oil looks dirty, the pump pulls a vacuum slower, the drying process takes longer, the shelf temperature rise slower than before (Yes, the shelf temperature change has to do with the vacuum), or a vacuum error message, it may indicate that gunk build up inside the pump may have partially clogged the pump. It is time to have a deep cleaning of the pump.   

In a previous blog we showed you how to take the front housing off the vacuum pump and clean the gunk inside. In this blog we go one step deeper and clean the cylinders that enclose the rotary vanes. The tools you need here are, a hose clamp (that comes with the machine) and a 1/16 and a 3/16 hex key ( you have to buy from somewhere), 

Assuming you have taken off the front housing following the guide in the previous blog. Here is a picture of the pump cylinder. It is secured by two bolts. 

Now remove the two bolts in the front using a 3/16 hex key.

Then use the handle on the hose clamp to pry open the round disks, 

And do this again to separate the two disks. You might see quite some gunk between the disks. 

The hose clamp handle can be used to scrub the gunk off the disk effectively. 

Notice that the holes and grooves in the disks. Particularly the one below, and red circles show the holes. 

You can use a thin 1/16 hex key to scrub gunk off the edges/holes in the disk. Notice in the image on the bottom right, it is a tunnel inside the disk which goes from the bottom of the disk to the hole in the red circle. Make sure you clean the gunk inside the tunnel. 

Use towels and vacuum pump oil to wipe clean the all the parts. 

And then re-assemble the pump, notice the orientation of the disk. There's only one way to put them back on, otherwise you won't be able to put the bolts in.