Breville Dual Boiler, five+ years on - Page 118

Need help with equipment usage or want to share your latest discovery?
pcrussell50 (original poster)

#1171: Post by pcrussell50 (original poster) »

sorenwrang wrote:Thanks for always being so helpful, Peter!
I will direct my focus towards the level of the pressure itself, making sure that the OPV setting does not limit my brew pressure.
Actually there is no harm in using the OPV as an extraction pressure limiter, and not only as a safety device. A lot of people use the OPV for this purpose these days in fact as low pressure extractions are becoming popular. In fact, lately I rarely do my own extractions even above about 7.5-8 bar.
sorenwrang wrote: I think it is getting close. When I brew 20g in, 40 g out in 30 secs, the pressure is around 9 bars initially.
Another thing that is also natural is that the pressure as indicated on the brew pressure gauge will naturally drop as the shot progresses. What happens is, as the puck erodes its flavors into the cup, it can no longer block the water flow enough for the pressure to remain high. So it drops lower and lower until the shot is ended. So you also have no problems or worries when you see this happening.

-Peter
LMWDP #553

sorenwrang

#1172: Post by sorenwrang »

pcrussell50 wrote:Actually there is no harm in using the OPV as an extraction pressure limiter, and not only as a safety device. A lot of people use the OPV for this purpose these days in fact as low pressure extractions are becoming popular. In fact, lately I rarely do my own extractions even above about 7.5-8 bar.
-Peter
I'm a little curious as to how you manage to brew at 7.5-8 bar and not end up with an under extracted shot. If I brew at that pressure, I'll have something like 20g in, 40 g out in 22-23 secs, which I think is quite fast considering the medium to light-ish roast I'm using..?

pcrussell50 (original poster)

#1173: Post by pcrussell50 (original poster) » replying to sorenwrang »

Remember what I told you about how the OPV can be used to limit the maximum pressure to 7.5 bar or anything you want? Well, I grind fine enough that the OPV would be working, oscillating just as you observed yours doing, not letting the pressure get above 7.5 bar.

My 7.5bar shots take 60-90s typically. Sometimes more. I grind so that I get that. So with that much extraction time, they are not under extracted. I also have done the Slayer mod, so I can slow down the flow toward the end of the shot, when the pressure is dropping and the flow is increasing because the puck is eroding away.

-Peter
LMWDP #553

pcrussell50 (original poster)

#1174: Post by pcrussell50 (original poster) »

Time for a periodic reminder...
Very satisfied owner of one of the expensive dream machines sez:
You do need regular maintenance and that can cost $100-$200 once or twice a year.
I change a ten cent o-ring every other year, and service my steam valve about the same... every other year.

Consider the bad mouthing the BDB has gotten for durability over the years, for only a fraction of the money and attention this machine needs. And yet when you own one of these "dream machines", you are happy to put up with it. And when the BDB requires less money and effort, its derided as being of "low build quality".

A little perspective about the color of the grass in other fields.

-Peter
LMWDP #553

ethiopianbuffman

#1175: Post by ethiopianbuffman »

Anyone find replacements for the inner shower screen in the US? I picked up a 6 yr old BDB and starting to dig into things I need to fix and this thread has been immensely helpful. Right now it is the inner shower screen (showing some cracking inside) and fix the steam valve as it is leaking. I am afraid of what the solenoid is going to look like right now, but will have to take it apart to see what wear is on it.

BaristaBob

#1176: Post by BaristaBob » replying to ethiopianbuffman »

Brandon,

Try eReplacementparts.com Here is the link to the part, looks like they are still available.

https://www.ereplacementparts.com/showe ... 10637.html
Bob "hello darkness my old friend..I've come to drink you once again"

pcrussell50 (original poster)

#1177: Post by pcrussell50 (original poster) »

ethiopianbuffman wrote:Anyone find replacements for the inner shower screen in the US? I picked up a 6 yr old BDB and starting to dig into things I need to fix and this thread has been immensely helpful. Right now it is the inner shower screen (showing some cracking inside) and fix the steam valve as it is leaking. I am afraid of what the solenoid is going to look like right now, but will have to take it apart to see what wear is on it.
Sounds like you have been doing your homework here, I'm guessing.

Some thoughts:

-You can use the brass disc from Amazon, which also comes with an IMS Competition outer shower screen, AND a Cafelat gasket. This is what I am using right now, even though I have a couple of stock plastic ones as well. One thing especially with the plastic ones: Do NOT over tighten. In fact they don't need to be very tight at all. I keep mine loose enough that I can turn the metal shower screen with my finger tips with some mild friction, but otherwise, turn it pretty easily.

-The solenoid form factor is standard with the rest of the industry. So any of the flat-base solenoids out there for other prosumer machines will fit and work. And some of them are higher quality than the original. I'm using one like that as we speak. (The bit you read here and there about all the "proprietary" Breville parts is a bit of urban legend. The parts that matter, are industry standard.)

-Have you read the thread and seen the video about servicing the steam valve?

-Peter
LMWDP #553

BaristaBob

#1178: Post by BaristaBob »

pcrussell50 wrote:Sounds like you have been doing your homework here, I'm guessing.

Some thoughts:

-You can use the brass disc from Amazon, which also comes with an IMS Competition outer shower screen, AND a Cafelat gasket. This is what I am using right now, even though I have a couple of stock plastic ones as well. One thing especially with the plastic ones: Do NOT over tighten. In fact they don't need to be very tight at all. I keep mine loose enough that I can turn the metal shower screen with my finger tips with some mild friction, but otherwise, turn it pretty easily. -Peter
Agree with Peter on the dispersion disc and the use of the IMS Competition screen...plus not to over tighten. Peter...are we okay with the brass disc being of dissimilar metal? Also with respect to group head temperature stability? Just wasn't sure where we all landed on these two issues.

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

pcrussell50 (original poster)

#1179: Post by pcrussell50 (original poster) »

BaristaBob wrote:Agree with Peter on the dispersion disc and the use of the IMS Competition screen...plus not to over tighten. Peter...are we okay with the brass disc being of dissimilar metal? Also with respect to group head temperature stability? Just wasn't sure where we all landed on these two issues.

Bob
Hi Bob. Ultimately, yes. I'm using it more and more and other than the mild steel screw being a little cruddy looking, seeing no issues. BUT I wouldn't just jack it in (too tight) and leave it for months that way. Mine comes off for cleaning and inspection about every couple of weeks, and I put a new wrap of plumbers teflon tape on the screw before re installing. Just in case.

again, for emphasis: ...make sure it's loose enough you can still turn the screen with your fingers...

-Peter
LMWDP #553

IMAWriter
Supporter

#1180: Post by IMAWriter »

DocPseudopolis wrote:Hello Everyone!

I have been considering a used BDB for my first machine purchase. I have already read this entire thread. But, I was wondering if there were any BDB specific questions I should ask sellers?

Already on the list
  • What type of water do you use
  • IS your steam wand nozzle leaking
  • What is your mx and cleaning routine
  • have you descaled recently?
Any other warning signs I should be looking at? I am targeting about $600 if I can find one locally.
We covered water a lot, but feel free to PM me and I'll send you the dr Pavlis water formula...eezy peezy!
Rob
LMWDP #187
www.robertjason.com