I am curious if there is a right and a wrong way to hook two rotary vein vacuum pumps together. One of our new welch crv pro 16 and an aging Edwards 28 were hooked together, simply, with a barbed T fitting. A one foot section of hose coming off each inlet to each pump was hooked to a simple barbed T fitting and then to an SPD system in hopes of getting “better vacuum”. Upon seeing this it made me a little nervous. The ultimate vacuum test on the Welch pump was in the high teens, low 20’s.
Does hooking them together in the way described above risk damaging either pump?
What would be the correct way to stack vacuum pumps to achieve greater vacuum or capacity to remove solvent?