BEWARE THE TRICKY ULKA PUMP?

I’ve been repairing coffee machines for a long time now and I already know that when it comes to flow issues in coffee machines, the pump is a prime suspect. But the other day I got tricked again and wasted an hour looking for a blockage in a Delonghi machine that did not exist. Just because I gave the pump the benefit of the doubt to save a few bucks.

I had the new flash Delonghi Primadonna Elite 650.55 MS in the workshop. Just the same old internals with additional Bluetooth and a colour screen. It was not running the rinse cycle or making a coffee. But water was flowing out the hot water spout just fine at a normal rate. In fact I had a great flow rate right up to the infuser group piston. After the piston just a few drops.
As the the pump was running super quiet and it was a recent 2017 edition, I assumed I had a blockage somewhere after the pump. And annoyingly I wasted a lot of time learning how to get into this Delonghi Primasdonna Elite to find a phanton blockage. The craft that crashed at Roswell was easier to get into than this thing.

So the take home message is. Ulka pumps may flow at a normal flow rate when not under pressure but when under pressure they can fail and produce no water flow at all. The pump will vibrate silently just as it would if there was a restriction in the line ahead of the pump. But the fault is with the pump, not a blockage further up stream. Replace the pump and the issue may well be resolved.

When you run a busy work shop and you are trying to reduce costs for customers, its hard to justify the time and cost of exchanging a pump that appears to be ok and is a 2017 edition just to eliminate it from your enquiries. But because the valves and group piston block are so hard to get at in these new Delonghis, I recommend changing the pump anyway. Don’t worry about the date on the thing, they crap out at any age now. Ulka pumps are not what they used to be. I am now sourcing the more expensive ones with the metal shaft. They utilise a different valve, I think its more reliable.

So if you have any coffee machine with a flow issue, but especially the new Delonghi’s. Yes clean the infuser filter clean the valves, clean all of the coffee line it all helps, but the pump may be the main issue and is always the right place to start.

Stephen Rodda

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