Breville BES920 persistent steam leak

Equipment doesn't work? Troubleshooting? If you're handy, members can help.
albionbrass

#1: Post by albionbrass »

As subject, changed the O-ring on the offending probe (the one with the Earth connection, at "8 o'clock" if you look from the front of the machine), but it still leaks. It seems to be coming from the top of the probe, where there is a gap between two metal parts.

I'm in the UK, so parts are not available locally, but it seems I can at least order new probes from Australia if necessary. But before I do, is there anything I can do to fix this? Machine is about 18 months old.

pcrussell50

#2: Post by pcrussell50 »

There are pretty much no steam leaks that cannot be fixed. Easily, unless you are referring the the filler tube on the side of the steam boiler. You should not need any new probes. They are not subject to wear, though the electrical spades can be damaged by scale or corrosion.

Is this the one you are talking about?


Is it leaking around the o-ring? If so, you might have the wrong size. It has happened before that people have measured their worn o-rings and come up with a size that is too small.

-Peter
LMWDP #553

albionbrass

#3: Post by albionbrass »

Hi Peter, thanks, yes that's the one. The O-ring I used was one of those black Viton ones. It's a lot stiffer than the original blue one, and took a bit of persuasion to go in. Might this be a problem? I've used them before on other BDBs, and they've been fine, but after what you said, I thought I'd change the O-ring again, this time with an original blue one. It has at least stopped spitting, but there is still a bit of a hiss. Is it worth trying two of these, or is that ridiculous?

The water is coming out of the bit between where the probe can rotate and move, and where it's fixed. There's a little bit of up and down play in it. Is this the normal place for the "standard" leak?

Thanks.

Dave

pcrussell50

#4: Post by pcrussell50 » replying to albionbrass »

Good morning Dave (morning for me :wink:

I have often recommended Viton to people because it is generally easy to find, and will stop the leak. However, I suspect it will not last as long as silicone or EPDM or AFLAS before becoming heat-hardened and passing steam again. For me, this is no big deal because I keep my machine without the screws holding down the top. So I can lift the top off for inspection or maintenance any time I like, at a moment's notice, without having to gather tools and remove screws. I kept the screws aside in a safe place for later use if need be. So changing o-rings for me is a non-event. I could do it every month if need be.

In the mean time, all of my sensors are "loose in the middle" like this one, which is the same one giving you difficulties:
It remans an open question as to why where is no steam leak for me and there is for you. But I suspect that they are meant to be loose like this. I wonder... If you were to put a dab of some elastomeric compound like polyurethane or silicone at the bottom of the ceramic sleeve, where the steel rod exits the ceramic, if that would slow or stop the egress of steam? Perhaps even a dab of food safe silicone grease (the kind that does not vulcanise) might be all it takes?

-Peter
LMWDP #553

User avatar
lancealot

#5: Post by lancealot »

This is a curious one. My sensors swivel like that too. It sounds like your steam leak is a function of the swivel seal (i just made that term up) and not the o ring. I don't understand the sensor swivel design so I can't really help fix it but I think Peters idea is a good start.

Let us know how it goes. I am curious to hear if you can isolate and determine for sure if it is coming from the o ring or the sensor swivel mechanism. I fear that it it is the sensor swivel, you may need a new sensor. But then again, lots BDB parts have revealed themselves to be user fixable. Maybe this is just the next thing for us to figure out! Good luck.

albionbrass

#6: Post by albionbrass »

Thanks for the replies. I'll persevere with the O-rings for now, in case I just got a couple of duff ones.

But how about this https://www.amazon.co.uk/TEMPERATURE-SI ... B00RY1RDMQ for the silicone sealant? Can you foresee any problems with effectively gluing a part that was previously free to move?

pcrussell50

#7: Post by pcrussell50 » replying to albionbrass »

That was what I suggested. HOWEVER, I consider it sub-optimal. I would rather find out a way to keep yours as they are. That is why before "gluing", I would try a dab of food safe silicone grease down at the bottom of the ceramic sleeve to sort of seal the small gap between the steel rod and the ceramic. That alone might be enough. Hopefully. You could also use silicone grease for scuba diving air regulators. I reckon that is food safe enough as well. In the USA there is Dow 111. But there are other brands too. Swimming pool silicone grease is the same thing, I think. Although it might not carry the "official" food safe label. Silicone grease is good because it is heat resistant, and it does not wash away in water. Even hot water. So don't wipe your fingers on your shirt or your wife will be cross with you because it will not come out in the wash. :wink:

-Peter
LMWDP #553

albionbrass

#8: Post by albionbrass »

Different O-rings do make a difference to the rate of steam escape and pressure required on the probe to cause the leak, so I'm hopeful that the problem can be solved with a dab of grease where Peter mentions, and maybe around the O-ring itself. Got some on order, will report back.

As ever, many thanks for the help.

Dave

pcrussell50

#9: Post by pcrussell50 » replying to albionbrass »

I should add that:

1) the only o-ring failures I have had in eight and a half years of BDB use are those associated with steam. I've never had a leak from a brew boiler o-ring
2) and even at that, I've never actually had any of the sensor o-rings fail/leak, even on the steam boiler. I suspect that over time, a kind of stiction develops on o-ring seals that would eventually result in a leak. A couple of weeks ago, I pulled out the sensors on my steam boiler after two and half years of continuous duty. They were NOT leaking. I pulled them out to examine and clean mineral buildup on the thin steel rods. But they had a little stiction when I pulled them out for the first time. If it had been bad, I could see how it could maybe damage an o-ring. I put them back with the tiniest dab of silicone grease to hopefully avoid any stiction issues in the future. The o-rings were fine and not leaking, so I left them alone. As I said, I've never had a sensor o-ring leak... even on the steam boiler.

-Peter
LMWDP #553

albionbrass

#10: Post by albionbrass »

I've put a bit of grease on the O-ring, at the top where the join moves and underneath where the probe meets the ceramic. I can get it to hiss very slightly if I prod the top whilst at full pressure, but it's a lot better than it was and will certainly do for now.