Breville Dual Boiler takes 2x as long to brew on the second cup?

Beginner and pro baristas share tips and tricks for making espresso.
yalag
Posts: 50
Joined: 2 years ago

#1: Post by yalag »

I recently found out theres something wrong with my BDB, it's only been 6 months old.

I find that the first espresso brews normally. I have the grind size where I want it to be, I always brew using the manual button. I time the brew to around 2x output and it finishes around 30s.

But then recently I tried making a second cup. Literally the same bean, same grind size, same dose. But the machine struggles with the second cup. It seems to not have enough pressure. The flow is really slow, and to get to 2x the output, it takes a full minute sometimes even longer.

I can't figure out why the first and second cup would be different?

BaristaBob
Posts: 1866
Joined: 6 years ago

#2: Post by BaristaBob »

That is strange behavior. I'd bet it's not the machine. To prove it, before extracting your first cup of the day, place a measuring cup under the group head and run it for 30 seconds and record the water weight. Then do the same before your second cup. If the water weight is the same I suspect your problem lies elsewhere. If they are extremely different, you have a machine issue that needs further investigation.

Best of luck.
Bob "hello darkness my old friend..I've come to drink you once again"

Advertisement
User avatar
Jeff
Team HB
Posts: 6808
Joined: 19 years ago

#3: Post by Jeff »

Guess - stale grinds in the grinder for the first shot

One test:

Grind two baskets
Pull the second basket first
If the "strangeness" flips, it's probably related to the grinder and retention
★ Helpful

yalag (original poster)
Posts: 50
Joined: 2 years ago

#4: Post by yalag (original poster) »

This is a good test. But how do I run the group head?

BaristaBob
Posts: 1866
Joined: 6 years ago

#5: Post by BaristaBob replying to yalag »

If your asking me about your water debit, you placed a cup on a rated scale under the group head and push the two cup button. Your water debit will show on the scale. I do this monthly the make sure my pump and the system is working properly.

If you're addressing Jeff, (and I think he's spot on), what type of grinder do you use and how do you collect your grinds...directly into the pf or a catch cup?
Bob "hello darkness my old friend..I've come to drink you once again"

yalag (original poster)
Posts: 50
Joined: 2 years ago

#6: Post by yalag (original poster) »

ok I never use the 2 cup button thats why I didnt know. Ok let me test that

I grind into a cup, and weigh it. I usually got for 17g each time.

BaristaBob
Posts: 1866
Joined: 6 years ago

#7: Post by BaristaBob replying to yalag »

For Jeff's test, first cup of the morning grind your dose into a cup and call that "Dose Cup A". Then grind immediately into a another cup and call that "Dose Cup B". Pull Dose Cup B first. Now, if Cup B (your first cup of the day) runs slow (like you described for your typical second cup) then stale beans are probably to blame (grinds sitting in your grind camber over night).
Bob "hello darkness my old friend..I've come to drink you once again"

Advertisement
User avatar
iploya
Posts: 705
Joined: 12 years ago

#8: Post by iploya »

I love mysteries like this. It is inherently incomplete information because we aren't there, so there's a chance we are missing some critical detail (one he may be unaware of).

I am not on board with the stale grounds theory. He says he is weighing 17g doses each time. The second shot takes twice as long as the first on the same grind setting. My bet is a machine issue.

You could try posting this in the Repairs/Restorations/Mods forum and let the BDB experts mull this one over.

BaristaBob
Posts: 1866
Joined: 6 years ago

#9: Post by BaristaBob replying to iploya »

I'm with you...love a mystery too. I'm also a BDB "expert"...6 years with my BDB, modded, changed most serviceable components at least once. So if the PO has a new machine (stated 6 months old) I feel it's highly unlikely it's the BDB, therefore, the answer lies elsewhere. Would like the PO to tell us what grinder he has.
Bob "hello darkness my old friend..I've come to drink you once again"

User avatar
bringyoutomyhell
Posts: 179
Joined: 8 years ago

#10: Post by bringyoutomyhell »

I noticed with my 64mm flat grinder that if I "single or double dose" the grind, the beans without the "weight" of other beans on top of them will be ground more coarsely and with less fines. I also noticed this when I was "bellowing" during grinding (I never do that now). I think it has more to do with the grinder than the machine possibly

Post Reply