New to home Espresso - Troubleshooting a Breville Double Boiler


New member
Nov 1, 2022
Sooke, BC
Hi everyone,

My wife and I recently purchased a Breville Double Boiler and a Breville Smart Grinder Pro to go with it. We've been purchasing week-old locally-roasted coffee from a couple of places (Stick in the Mud in Sooke, and Discovery Coffee in Victoria. Both are amazing if you're ever on Vancouver Island!).

We've managed to get our single shots dialled in quite well. A 14g well-tamped dose (grind size "10" on the smart-grinder) starts pouring around 9 - 10 seconds, is stable at 9 bar during extraction, finishes at 30 seconds, and is super-tasty. We're happy here.

We're now struggling to get our double-shots to work... at all. I'll switch to the double-shot basket that came with the machine, put around 18g of grind-size "10" espresso in it, and ... might, maybe, be lucky if the machine gets up to 3 bar... Usually just 1 or 2 bar... (To be very clear: Same beans, same grind size. We just put the double-shot basket in, and use an 18g dose.)

I presume everyone can imagine what they taste like.

Yes, we have tried "a bunch of stuff" including changing grind size, larger/smaller doses, even some different beans (though we've gone back to using the same stuff for consistency while we learn...) ... We keep getting similar results. I haven't had huge amounts of luck changing the grind size by 3 - 6, or by changing the dose from around 17 to 20. (above about 20 starts to be too much, and to literally push into the group head, which I presume is bad...

As soon as we go back to our single-shot basket and 14g, everything is fine. It's JUST the double-shot basket that is giving us struggles.

I feel like I'm just flailing at how to problem-solve this now. All the "how to dial in your espresso" videos I can find seem to talk about how to fine-tune your shots after things are working mostly-normally, which is really not-at-all the case here.

Can anyone help a newbie by offering some suggestions, or pointing us in the right direction? I'd be most grateful!



Well-known member
Aug 15, 2005
Central North Carolina
Dunno about these days, but for some time the BDB came with 2 types of baskets. A single/double that are SINGLE wall as in standard/non-pressurized and a single/double that are DOUBLE wall that pressurizes the system so a less precise grind quality/stale coffee can be used for tolerable results. The double wall will usually have one hole on the bottom, whereas a standard will have lots. This sort of thing does confuse many that seem to have issues. Not saying that's your problem, but is a common thing to mention as a starting point. ** I mention this as you reference a 'single' shot as being 14 grams, when a typical true single basket might hold 10 grams max based on what I've used**

Also, numbers on any grinder are for a point of reference and not much else. Best thing to do is use the same coffee, dose weight, etc. and grind finer each extraction until it starts to stall a bit, then back off a bit more coarse and make small tweaks to get the taste/texture you like. Keep in mind this will vary with every type of coffee you try, even the same exact coffee just a different/fresh batch. Coffee will age by the day and require small tweaks to keep dialed in. Even a 10% change in room humidity can affect things drastically.
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New member
Mar 30, 2023
Use a kitchen scale. With 1:2 ratio 18 g of beans going in should give 36 g of espresso. Don't depend so much on grind size at first. Get the output. If pressure is low, try larger grind to see if it gives the output. It should take 25 - 30 sec, but time can be off. Make sure to use double shot single wall basket. And tap it to get rid of empty pocket in the grinds.