You pull a shot, knock out the puck, and the group head keeps dripping. Maybe it’s a few drops. Maybe it’s a slow, steady leak that’s still going when you come back from steaming milk. One of those is fine. The other one is a part wearing out and telling you about it. Knowing which is which saves you a service call you don’t need, and tells you when you actually do.
The normal kind
Right after you stop a shot, there’s still pressure built up in the group and in the coffee puck. The machine has to let that pressure go somewhere. On most commercial machines, a valve opens and dumps that water and pressure out the bottom of the group. That’s why the puck comes out as a firm, dry-ish hockey puck instead of a wet mess, and it’s why you’ll see a few drops fall in the first second or two.
So: a short burst of drips right after the shot, then it stops. That’s the machine working the way it should. Don’t fix what isn’t broken.
The kind that means something
Here’s the tell. Stop the shot, walk away, and come back a minute later. If the group is still dripping, or worse, running a thin steady stream, the machine isn’t sealing anymore. Water from the boiler or the line is bleeding through the group when it shouldn’t be.
On most modern machines, the part doing the sealing is a three-way solenoid valve. It does two jobs: it sends water to the group during the shot, and it releases pressure after. When it wears out, it stops closing all the way. Now you’ve got a slow leak that never quits. Coffee grounds, scale, and just plain age are what kill these valves. They’re a wear item. Every busy machine eats through them eventually.
If your machine is a lever group, or an older traditional setup, the steady drip is more often a worn group gasket or a tired piston seal. Same symptom, different part. That’s why guessing from across the counter doesn’t really work. A tech needs to see whether you’ve got a solenoid bleeding through or a seal that’s given up.
Why you shouldn’t let it ride
A drip feels minor. It mostly is, at first. But a group that leaks all day costs you in ways that add up.
Your boiler refills and reheats every time it loses water, so you’re paying to heat water that’s going straight down the drain. The runoff pools under the group, and that’s the worst spot for it, because the solenoid, wiring, and connections all live right there. We’ve opened up machines where a months-long drip rusted hardware and shorted a connector that turned a cheap valve job into a much bigger one. And a leaking group can throw off your shots, since the valve that’s not sealing after the shot may not be doing its job during the shot either.
So it’s not an emergency the day it starts. But it’s the kind of small thing that turns into a big thing if you ignore it for a season.
What to check before you call
A couple of quick things are worth ruling out, especially if you’ve got more than one group and only one is dripping.
First, back-flush the group with a blank basket and detergent if you haven’t lately. A wad of old grounds stuck in the valve can mimic a worn valve, and a good clean sometimes clears it. Second, look at whether it’s one group or all of them. One group dripping points to that group’s valve or seal. Every group dripping at once points to something upstream, like pressure or a fill issue, and that’s a different conversation.
If a back-flush doesn’t fix it and the drip won’t stop, that’s your sign. The part’s worn and it needs swapping.
When to call us
If you’ve cleaned the group and it’s still dripping a minute after the shot, that’s a worn valve or seal, and it’s a real repair. The good news is it’s usually a fast one. Once a tech sees which part is involved, most group-head drips are a same-day fix. We stock the common three-way valves and gaskets for the machines we see most around here.
We’re at (925) 999-4095, 7 days a week, 7AM to 7PM, covering Dublin, Pleasanton, Livermore, Walnut Creek, Concord, Oakland, Berkeley, Fremont and the rest of the Tri-Valley and East Bay. Diagnostic is $75, and we waive it if you go ahead with the repair. If your group’s gone from a drip to a stream, take it offline and give us a call. The other groups can keep you running while we sort it out.