Tal Edit: have reassembled as above and believe that is correct
https://coffeetime.freeflarum.com/blog/2996-vesuvius-vacuum-breaker-oring
Vesuvius Pressure Profiling Machine - General Discussion
Cuprajake It wont seal till it reaches pressure, so some steam and water is normal.
It’s a memory metal vacuum breaker, these seal on temperature… so much earlier than normal vacuum breakers
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Ok interesting, much appreciated.
I’ve just descaled the fill probe as per Paolos advice and that looked fine to me. I may have disturbed that little spring, or O ring as it now takes 1.3 to 1.4bar to seal, whereas before it was sealing around 0.9bar. I’ll take it apart again and check it works with boiling water as per above.
I did find a leak in a hose though, hard to see, but the dark line is a tiny split. Is this hose bought with the flanged ends? Or is it an feature of the compression fitting to spread it out, so if I trimmed the line back a little and refitted it?
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Opened the vac breaker again. O ring looks ok to me, but going by Dave’s link above maybe it needs changing anyway. I’ll order a set of seals to be sure.
Spring also works well, expands in hot water etc. have cleaned it up again and refitted. Will take it off again once I sort some seals.
Edit: just cut the leaky pipe by trimming around 10mm off, I think I will get some PTFE tubing and replace this short run. It’s rather tighter than I would like now.
Just turned it on. It now stops the steaming from the drip tray at a much more modest 0.7bar, before I started this it was 0.9 to 1bar, and just now before taking it apart a second time it was up to 1.4bar before closing so we are winning, o ring hopefully will sort it.
Cheers
Tal I did find a leak in a hose though, hard to see, but the dark line is a tiny split. Is this hose bought with the flanged ends? Or is it an feature of the compression fitting to spread it out, so if I trimmed the line back a little and refitted it?
The flange is formed by the compression of the fitting. To remake he end all you have to do (and it sounds like this is what you did), is trim the end off with a stanley knife.
Obviously my initial suggestion was wrong and i no longer have a pressure profiler, so, what is that connector. Does it have a non return in it that can also need cleaning or replacing?
Ade Smith. ACS Evo Leva v2. Kafatek Flat max 2, ssw 2024. Mazzer Philos, Craig Lyn HG-1 prime., WW key mk1.
Paolo has suggested I change the vacuum breaker (anti vac valve) and the fill level sensor, so I am getting a quote for those, but I may try and get a new seal for the vac breaker as well, incase it saves me scrapping an otherwise working part. I did measure the amount of water that enters the drip tray and it was near 50g, that doesn’t include any water emitted as steam.
@Adrianmsmith , Paolo has suggested that the connection that we identified as leaking (well the hose was leaking), that this delivers water to the group. Perhaps it is to do with the “HX on” option, where it utilises the HX circuit to assist with heavy work load scenarios.
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While I am awaiting a quote from Paolo, I decided to take apart the vac breaker again and measure the O Ring seal. As numerous searches didn’t throw up anything unanimous.
Measured - Wall thickness 1.73mm, ID approx 9.5mm (measured the recess in the vac breaker seal seat), OD approx 12.5mm.
Cross referencing these with BS sizes shows the closest size is:
BS012 - 1.78mm wall thickness, 9.25mm ID
Ordered some of these, should hopefully be here by the weekend.
When I reassembled the vac breaker with the original seal I added a smear of Molykote 111 to the O ring. Brought the temp at which the valve closed down to 112C (0.6bar). So a fresh seal could sort it out. Fingers crossed.
As the Moly 111 arrived today I also decided to back flush with Caviza. I get the impression the previous owner never back flushed with cleaner. Only hot water, so was expecting it to be a little rough. The back flush water was coming out very dark!
Then I opened the cam chamber up following DaveC tutorial earlier on in this thread, cleaned it all out and re-lubed the pins, cam and shaft. Lever is slightly squeaky now within the group. I assume I’ll need to remove the pin assemblies and re lube those completely. As well as possibly polish up the cam and relube to ensure everything is operating smoothly.
Edit this morning the vac breaker sealed at 0.3bar, getting better
Edit2: think the Molykote has been displaced as we are back to 0.7bar to seal. Hoping seals may come this morning (28/05) or tomorrow latest
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Ok, seals for the vac breaker arrived today. Just fitted one and the boiler sealed itself up at 108C, 0.3bar.
I’m happy with that, I didn’t use any Molykote this time as I’m sure it just got washed away with steam last time. Assume a perfect/new vac breaker valve would close at exactly 100C?
Cheers
Tal Assume a perfect/new vac breaker valve would close at exactly 100C?
Not necessarily net necessary 😎
Approx 101 yeh but theres usually a little bit of a hiss and condensate in the drip tray and questions on facebook “should i see drips of eater from that thingy at the back of the drip tray when my machine is warming up” 100000000’s of the same questions. Along with should the centre bolt of my niche zero come loose if i dont tighten it properly 😎
Sometimes on the synchronika it closed early and you would get 2.6 bars showing untill you gave it a quick purge to remove the trapped air and a little steam.
Ade Smith. ACS Evo Leva v2. Kafatek Flat max 2, ssw 2024. Mazzer Philos, Craig Lyn HG-1 prime., WW key mk1.
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I could save myself £50 on a new vac breaker then! Paolo not replied yet. Assume he’s struggling to get a price. But I can find one here: