Breville Dual Boiler Mods and Maintenance

Need help with equipment usage or want to share your latest discovery?

#1: Post by pcrussell50 » Nov 02, 2019, 4:57 pm

So, I was going to put a bunch of helpful links to mods and common maintenance (which is oddly about all that ever seems to be necessary on these machines to keep them running), on the first page of the: Breville Dual Boiler, five+ years on which has kind of become a de facto "BDB owner's thread". But Dan suggested that since that thread was already huge, maybe I start a new one, with a bunch of helpful links on the first page.

I expect this to be a work in progress in case anyone else who is a marathon BDB owner discovers the so far elusive, big unfixable problem. So here goes:


What you will face going forward, (and this applies to any machine you may one day have in your espresso journey): Any machine that deals with hot, pressurized water, in the presence of electricity, is going to have certain maintenance requirements. There are generally two philosophies in dealing with this. Preventative maintenance, and "fix as you go". Breville is very much a "fix as you go" type of company, and thankfully, waiting until something breaks rarely comes with any kind of serious damage on this platform. The only pitfall is a psychological one... By not doing preventative maintenance, things will break. And when things break, people tend to think their Breville machine is junk and seek something else. Then they spend four or five times as much for a La Marzocco or such, where you do expensive yearly PREVENTATIVE maintenance, so that things don't break (as often). And guess what? Then people are even more certain their Breville is junk. But this is a big logical mistake of course. And leads to incorrect conclusions and beliefs about the durability of these machines.

All maintenance and repair begins with removing the top cover: See: "Removing the top and accessing the innards" here: ... 603#716603 Once the cover is off, don't bother trying to disconnect all the wires from it. Just find a way to prop up the cover out of the way, without straining the wires.

Use scale free water. IOW water with no calcium or magnesium (the components of scale). Or water with low enough Ca or Mg AND a pH that prevents scale formation. See this post: Breville Dual Boiler Mods and Maintenance

2) Drippy steam valve
The steam valve on all these machines eventually develops a slow drip when warmed up. Sometimes in as little as a year, sometimes two or three. There is a thread here on HB discussing all about it and before we figured out how easy it is to fix, a bunch of posts about possible solutions. Cutting to the chase, the easy, no parts fix: Breville Dual Boiler ball valve detail, pics. If you don't ever want this to happen to you, pretend it's a La Marzocco or other high end machine and flip the seals every year. As with other BS myths about proprietary non-user-serviceable parts, you can also buy replacement seals on Amazon for next to nothing for a bag of 100. But by and large, you don't need them. Just keep flipping the ones you have.

3) GFCI tripping, runaway heating
Sounds terrible. "This machine is a disposable appliance grade POS" Right? Wrong. Easy fix, almost free. OR easily preventable if you choose that route by changing your o-rings every year or so like La Marzocco. What is happening is that common silicone #007 o-rings sealing the 4mm PTFE water tubes into the top of the steam boiler need replacement. Once the insides dry out and you have fixed the leaks with new o-rings, normal operation resumes. A bag of 100 of these size #007 o-rings is $9.99 on Amazon. Your children will be dead of old age before you run out. Detailed thread: ... 603#716603 Since early-mid 2018 Breville changed the method of sealing the PTFE water tubes on top of the boilers to some other scheme that looks more robust than the o-rings. We do not know when or if they will leak, or what to do about it if they do. Too early to tell for these newer machines.

4) The solenoid. Starts getting "buzzy" for some people after two or three years. Might be due to scale. I remove and inspect mine about once a year. But I use scale free water so not had any problems or cleaning to do under the base of the solenoid. If you need to replace it, Open the cover and direct replace. But a new one here: ... 39484.html This is a standard Lucifer base solenoid, so any other Lucifer base solenoids should work, too like the one from the Silvia.

5) The pump. Rarely needs replacement. But As with other BS myths about proprietary non-user-serviceable parts on the BDB, it uses the same Italian Ulka vibe pump as any other prosumer vibe pump machines out can also buy replacement pumps on Amazon for next to nothing. ... 00NMNA138/

These are pretty much the only common items that wear out and need repair. One more general catch-all thread for repairs: ... nes/726101


in progress... links to follow text. check back later

Flow and Pressure Profiling

In order to keep this post from becoming huge, I expanded this section in a different post of this thread: Breville Dual Boiler Mods and Maintenance

Three ways:
1) Straight out of the box, this machine already has programmable pre infusion. This is more and better than almost all of the high end machines on the market. And it has full manual override of time. So if you want to pre infuse not according to a pre set time, but rather, until is "looks right", you can do that too.

2) If you want more, you can move a microswitch out of the way and get current model conical valve GS/3MP style pressure profiling, in which the excess is vented to the drip tray. Not very elegant, but it works. A few posts down, here: Breville Dual Boiler Mods and Maintenance
3) If you want to go whole hog, you can do what we call the "Slayer Mod", which gives you beginning to end flow control, without venting/wasting to the drip tray. This is actually better-than-Slayer level control over flow. (2) is so easy it's a joke. You can't really even call it a mod. This one (3) is just easy. A few posts down, here: Breville Dual Boiler Mods and Maintenance

Plumbing and conversion to Rotary pump
Easily done, with no permanent changes to the machine itself. About as easy as installing an under-sink softer filter and plugging it's output into the pump, then running that to the back fo the BDB. The difference in quietness and refinement cannot be understated. A HUGE aesthetic upgrade.

Brass OPV and brass necked pump
If you aren't ready to commit to plumbing, (which must be done to go rotary), the brass necked pump and brass OPV give a much more refined, damped, and quieter sound and feel. Nowhere near rotary level. But something.

This video demonstrating the rotary pump AND flow control. About halfway through the pull, I speed the flow up and towards the end, you can see I slow the flow down (the way everyone should as the puck erodes... If your machine has the capability):
LMWDP #553
★★ Quite Helpful


#2: Post by Quester » Nov 02, 2019, 6:24 pm

Awesome. Thanks for posting this.


#3: Post by mr2andy » Nov 02, 2019, 11:01 pm

Great stuff!!!


#4: Post by pcrussell50 » Nov 03, 2019, 2:25 pm

(First, the crude and easiest way...the MUCH better, "Slayer mod" method to follow in a different post)

Flow and Pressure Profiling EXPANDED WITH PICS AND VIDEO ITEM (2) The pressure bleed/GS/3MP method
(the MUCH better, "Slayer mod" method to follow in a different post)

2) If you want more, you can move a microswitch out of the way and get current model conical valve GS/3MP style pressure profiling, in which the excess is vented to the drip tray. Not very elegant, but it works.

The way this works is, you bleed off pressure during the pull by opening the water tap. This sends the un needed water through the tap and into the drip tray in much the same way as the GS/3MP with the conical valve. In order to have full authority, you have to remove the top cover and move the microswitch from behind the water knob. This is super easy.

here it is under the two partially loosened screws:

remove the screws and pull out the switch and the holder:

here is the switch. on mine, I just zip-tied it out of the way:

video of it in action. with stock vibe pump. you can catch glimpses of the extra water going out the tap into the drip tray:
LMWDP #553


#5: Post by pcrussell50 » Nov 03, 2019, 5:39 pm

And now the big dog...

Flow and Pressure Profiling... THE SLAYER MOD

With this one, you have direct control of flow and pressure at the puck, from the tiniest trickle, all the way up to full flow potential of the pump and anywhere in between. It's this second bit, the bit about anywhere in between that is actually something Slayer can't do. Slayer has "two speeds" high and low. With this mod to the BDB, flow is continuously variable anywhere you want in between. And as different from the "GS/3MP mod" above, there is no excess water wasted when you are not using full flow. It all goes through the puck... just at any flow rate you desire.

So, how do you do this? Not quite as much of a no brainer as simply moving the microswitch. But not much worse. It is a simple plug and play re route of a couple of the existing PTFE tubing, and cap off an unused water line. No cutting or permanent modding. All easily reversible put back to stock for factory repair if you should ever need it.

First, from post #160 in the BDB Slayer Shots thread, my eureka moment when I first did it: Breville Dual Boiler "Slayer shots"?

Skipping ahead to post #165 the textual description of how you do it: Breville Dual Boiler "Slayer shots"?

How it looks under the IMS screen, going from slow, to super slow, to open (before conversion to rotary):
How it looks on the group pressure gauge pulling a shot with a long Slayerlike pre infusion, slow ramp, then slow decline (also before conversion to rotary):
Pics of the tube routing: Breville Dual Boiler "Slayer shots"?

Improved way of capping the unused water line: Breville Dual Boiler "Slayer shots"?

And finally the coup de grace...Andy's video of the mod (note in the video, he had not yet moved the microswitch of the water knob, which is the first thing you should do):
LMWDP #553
★ Helpful


#6: Post by Valo_Soul » Nov 03, 2019, 10:11 pm

Just wanted to send a huge, sincere thank you. Excellent post!


#7: Post by gchapman » Nov 05, 2019, 9:27 pm

Thanks for this, Peter, and for all your pioneering work. A great help to all of us BDB owners.
Geoff Chapman


#8: Post by pcrussell50 » Nov 06, 2019, 3:43 pm

Re water and it's importance to durability...

If your yearly inspection of your solenoid doesn't look like this, you need to address your water situation:

This is five years worth.

LMWDP #553