Breville Dual Boiler ball valve detail, pics - Page 20

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

#191: Post by jfjj »

gchapman wrote: Looking from the other side, here is the black seat of that seal.

i had a long flat head needle that I used to gently push the seal out of the valve.Prying it out would probably damage the seal.
- Jean


#192: Post by gravity48 »

Came here to thank all those who had posted clear photos, tools required, and break-downs. I was able to flip my seals fairly easily (had to loosen the central valve in hot water before it opened). Thanks so much!

Afterwards, the o-ring started to leak, so I've next gone and ordered an EPDM o-ring from a UK supplier ( ... _info.html). Amazon doesn't carry o-rings like the 007 in the UK, so I had to look around for a while to find these guys.

Fingers crossed that's all the DIY I have to do for now.

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#193: Post by luvmy40 »

Another thanks to Peter, Jake and all others who have compiled such a great resource for the BDB!

I just flipped the steam valve seals in my BDB. It was leaking very slightly. Just enough to be annoying, but it was time to open her up and inspect for leaking o-rings so it seemed to be a good time to stop the drip.

BTW, no sign of leaking seals anywhere.

pcrussell50 (original poster)

#194: Post by pcrussell50 (original poster) »

luvmy40 wrote: BTW, no sign of leaking seals anywhere.
It's usually only the seals that use o-rings and hairpin clips that leak, and at that, usually only the ones that are holding back steam. On the mid-2018-newer machines, several of the notorious o-rings have been done away with in favor of tube nuts. There have been no reports of leaks from those yet. From the look of them, it may be a very long time if ever, before they leak.

LMWDP #553


#195: Post by harleymc100 »

If anyone is interested i "repaired" my leaky ball valve.

As above, i removed the internals, cleaned everything up and noticed "wear and tear" which was probably due to thousands of actuations.
I assume it had compressed the washers supplied so i took a very thin stainless steel washer and inserted it on the flat side of the white washer. i thread taped the screw on hex part of the valve until it was firm. Leak tested with compressed air at 8 bar for half an hour with no leaks.
So far so good. Its basically a free repair.
If anyone needs more information on this feel free to contact me here.

pcrussell50 (original poster)

#196: Post by pcrussell50 (original poster) »

This will work too. But it is more trouble than necessary. You don't need the thread tape or the steel washer behind the flat side. This would be necessary if the seals were not made of such a special and unique material. In the end you don't need to add any more stuff than was there originally. The valve is simply resealable. Nothing needs to be added.

BUT... All you actually need to do is flip the PTFE seals/washers over, so the flat side is against the ball (and the conical side is away from the ball).* When you screw the two halves of the valve body back together you don't screw them all the way. You just screw until you have the feel good friction when you open and close the knob. In another year or two when it drips again you can screw back some more. Then in yet another year or two screw some more. When you finally run out of threads to screw more, flip the seals again. And so on.

*The reason this works is that the PTFE material that the seals are made of, behaves like a thick liquid and the flat side will form itself over time into the same conical shape as the ball. It is important to note that you do NOT need a conical shape to form the seal. The seal is made by a "line" of contact, not a "surface" of contact.

LMWDP #553


#197: Post by jevenator »

I just flipped my washers in the steam valve assembly as I was getting small pools of water.

It took me like 80 minutes to figure out how to take it apart because I couldn't find step 1...step xx. Figuring out how to take off the steam lever was a pain until I came across your album, Peter. That helped out and gave me the aha that I needed to take off the micro-switch and then push it off. I needed a right angle screw-driver to reach the plate that held the steam valve against the wall of the machine. It was too tight for me to go head on and if I took a smaller driver I couldn't generate enough torque with my fingers.

Nevertheless, everything else was pretty easy and nothing was seized or stuck just took a little bit of muscle.

I found that I don't have to take off the bottom retaining clip and can just pull it off. Saves you the time of unscrewing the hot water valve + steam wand assembly plate to get a good grip on that retaining clip.

Fired up the machine and no more leaks! Although, my washers were very concave. Will I need to get new ones later down the road? Can anyone that bought a whole bunch from amazon just send like 4 over snail mail :D I feel like that will last a long time haha.

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pcrussell50 (original poster)

#198: Post by pcrussell50 (original poster) »

jevenator wrote: Fired up the machine and no more leaks! Although, my washers were very concave. Will I need to get new ones later down the road? Can anyone that bought a whole bunch from amazon just send like 4 over snail mail :D I feel like that will last a long time haha.
Now, over time, the flat side will become concave, and most likely the concave side will become flat. That is the nature of PTFE, which behaves like a thick paste or super thick liquid. Under pressure it flows to conform the the shape of the forces being placed on it.

This concave look you see was flat as a pancake when I flipped it and screwed the valve halves together 24 hours prior to when I took the pic:

Note: I did not screw both halves of the valve body all the way. You only need to screw it so that you get a good feel of friction when you actuate the valve knob.

LMWDP #553

pcrussell50 (original poster)

#199: Post by pcrussell50 (original poster) »

Video how-to, flipping the PTFE seals to stop the drip:
LMWDP #553


#200: Post by DaveB »

Thanks for the video! Is it intentionally silent? A bit of running commentary might be helpful.
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