HB wrote:I assume cost and size are the decisive factors. Many one group cases simply cannot accommodate the size of a motor and rotary pump. Some manufacturers manage to squeeze them in, but that can mean working in cramped quarters when it's time for repairs and adjustments.

Costwise, a vibe pump seems like poor economy on high end prosumer machines. It's a deal breaker for folks like me. Sizewise, it makes sense - especially if the target audience demands a small case and/or a water reservoir as a pourover option.

JonR10 wrote:Respectfully I say "bullcookies" Why would you suppose that not a single commercial espresso machine manufacturer uses vibe pumps in their commercial products? Not one! Plus, a new rotary pump for an espresso machine is generally under $150, so I don't know where this "hundreds or dollars" for a replacement comes from.

What are the odds, I've only worked on two commercial machines and both used vibe pumps. La Cimbali used vibe pumps in their older Junior Ds and La Pavoni uses them in their 1 group pour-over Pubs.

Multi-group machines have to use a rotary because a single vibe pump can't generate the pressure for two shots at one time but I don't see the big deal about using them in a light usage 1 group machine. Sure vibe pumps fail. But I've seen enough 10 and 15+ year old pumps so that I am not worried about their reliability. That said, I could design a machine that would need frequent vibe pump replacements. Mount the pump right next to the boiler and heat would bake the rubber and plastic parts. But that would be silly.

Wesley

coffee_no_sugar wrote:What are the odds, I've only worked on two commercial machines and both used vibe pumps. La Cimbali used vibe pumps in their older Junior Ds and La Pavoni uses them in their 1 group pour-over Pubs.

Fair enough, my statement was wrong.
Some light commercial (i.e. pourover) machines use vibe pumps.

I have had a couple of vibe pump machines and a couple of rotary pump machines. I have had one vibe pump fail and no rotary pumps fail. Both have generally been reliable. The difference in the perception of quality with the rotary, in terms of general feel and lack of noise, is enough to make me love the rotary machines and not want another vibe pump machine if I have good alternatives.

BillK

FYI, the Double Domo (VBM double boiler) can be had with rotary.

There have been a few studies comparing vibe to rotary on identical machines and the tests were inconclusive. The testers did not note any difference between the two.

Vibe pumps are relatively reliable, there is something unusual going on with John's experience of constant burnout, could be just bad luck. I have run vibe pumps for 3 years and never had any issue. I have both vibe and rotary pump machines and like them both. Each has it benefit but either will serve the purpose. At home where plumbing in a machine is relatively easy, I like my rotary. The solenoid snapping open is noisier than the pump. In my office, I like the vibe because space is a premium. The machine does not have to be enlarged to make room for an on board rotary and I don't want a 5 gallon bucket sitting on my desk to feed the machine.

JonR10 wrote:Fair enough, my statement was wrong.
Some light commercial (i.e. pourover) machines use vibe pumps.

fwiw, cimbali use vibe pumps in 2gr commercial models too. I have 2x m31 in my 'shop now (for reasons unrelated to their pumps ).

The Italian manufacturers I've talked to use vibe pumps for tank machines, rotary pumps for plumb-ins. Simple as that. All of them recommend that rotary pump machines should only be used when attached to a permanent water supply.

In my own experience, you KNOW when a vibe pump is running dry by the sound. You find out when a rotary is running dry when the tech gives you the bill.

Alan

Alan Frew wrote:In my own experience, you KNOW when a vibe pump is running dry by the sound. You find out when a rotary is running dry when the tech gives you the bill.

I've run a rotary dry (from a tank) for a total of 1-2 seconds. By accident. And you can definitely tell from the sound! Granted, it's not as impressive as with my old vibe machine, but it's pretty obvious - gurgling, and loud.

(I disconnected and reprimed the pipes inside the machine before restarting - and it sounds back to normal now ).