When you’re considering the purchase of an espresso machine there certainly is a lot to consider. One detail that has become more popular is the option to have a rotary pump in your espresso machine as opposed to a vibration pump. Rotary pumps are available in a lot of our high end prosumer machines. It is quite often debated which of the two types is better. As with many debates, there are valid arguments in support of both types of pumps and no clear answer as to which is better.
There are a few things to discuss regarding the pump and the first thing discussed is going to be reliability. In order to examine the potential for problems let’s look at how each pump works.
First the Vibration Pump – Vibration pumps utilize oscillation to move a diaphragm which moves the water. A spring piston vibrates back and for the forcing the water through a one way check valve and then to the machine. It is a simple and well designed system. Most vibration pumps are made by Ulka and have had a great track record. The advantages of a vibration pump are as follows
- Much cheaper to replace
- Take very little space
- Will not get damaged if run dry as they are self priming
- Create a natural pre-infusion as they ramp up to pressure
- Less likely for mineral deposits
Next let’s look at the Rotary Pump – Rotary pumps operate a little differently, utilizing rapidly oscillating vanes inside of a sealed container to push water at high pressure. The pump may also be adjusted to change pressure as well. Lets look at the advantages of a Rotary pump.
- Much quieter
- Ramps up immediately to pressure
- More commercially built
- Designed for higher volume.
- Better suited to plumb in your machine.
That explains the differences in the pumps. The most interesting thing in my opinion is that both will produce excellent shot, there should not be a difference in the quality of the shot based on the pumps. I do think the rotary pump, besides being quieter, is better suited for back flushing your machine. I also think plumbing in your machine and putting a great water softener/filter are the best things you can do for it.
When it comes down to making a purchase, the most important thing is to not really worry so much about the pump but to get the machine you really want. If you want to make great espresso they both work well............................