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Vesuvius brew boiler heating element replacement

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I provide below a description of the process I went through to solve the problem of a ruptured brew boiler heating element on my Vesuvius.



I’d had the Vesuvius for maybe 2 months when I started to notice the brew water had become very cloudy. When I was sure the water was actually always coming out cloudy, I stopped using the machine and asked for help on the forum. Whilst everyone was helpful, I was convinced the problem was not the obvious: needed a good clean, e.g. start backflushing regularly; what kind of water are you putting into it? The water was just too cloudy for these helpful suggestions to be the cause. After leaving a glass of the output cloudy water for several hours, it would eventually clear leaving a fairly significant residue of fine white powder in the bottom of the glass. By the way, it was only the brew water that was cloudy; water from the steam boiler was clear as a bell.


After a bit more pondering, I decided I needed to open up the brew boiler and see what was inside. The only way to do this is to remove the heating element. After contacting @DavecUK to ask advice, he told me I needed a 36mm box spanner, and even gave me a link to Amazon:



where they were on sale for £12, pretty good price I thought. The tool selection is pretty crucial. The base of the heating element is recessed by a few inches into the body of the machine. There is no room to use anything like an adjustable spanner - you need a box spanner or socket to get in there with the necessary leverage.


Vesuvius box spanner.JPG


To gain access to the brew boiler element, I lifted the machine onto a pair of benches, so I could access it from underneath while I was lying on the floor - front of the machine on one bench, rear on the other. Removing the base plate was easy using an allen key on the bolts. The brew boiler is the smaller of the two boilers.


Vesuvius base.JPG


First remove the two push-on electrical leads. Removing the element with the box spanner was not difficult as it is not screwed on hugely tightly. You need to unscrew it carefully and slowly to allow the water to drip out at a controlled flow, so that it just drips out onto the floor, i.e. without soaking anything else near at hand like bits of the machine and electrical contacts.


I found the culprit immediately. The element had ruptured and was spilling its contents, magnesium oxide white powder, at a steady rate into the boiler.




I contacted Paolo at ACS who agreed to supply me with a replacement heating element. After allowing the boiler tank to dry out for a few days, I used a small brush to remove the remaining white powder at the base of the tank.


Vesuvius new element.JPG


The replacement element was easy to install using the box spanner again. However, I did find it difficult to know how tightly to screw it in, as the screwing in became tight quite quickly, and, as it turned out, before it was fully secured in place. I then powered the machine up and followed the instructions in the manual on how to fill up the boiler from empty. This worked but I found the boiler was leaking quite significantly, so I switched off the machine and let it cool for a few minutes. I then tightened up the element, which now felt looser and easier to screw in. I then left it to cool for several hours to see if any more leaks occurred, since the tank had now filled up. It did continue to leak in slow drips, so I continued to tighten it up until no further drips, leaving a piece of kitchen paper on the floor under the tank overnight to check.


I then proceeded with the instruction manual, drawing 1 litre of water in 200ml amounts through the group head. The first 200ml was a bit cloudy. When I’d got to the last of the five 200ml amounts the water was completely clear - to my great relief. Problem solved!


I then replaced the base plate and replaced the machine on the worktop for normal use. I left a piece of kitchen paper under the machine to check for any drips over the next few days. My first coffee out of the machine was delicious, after a five week period without!


Whilst this problem was a bit difficult to diagnose initially, I’ve got to thank everyone for chipping in with suggestions. Particularly, I have to say a big thank you to @DavecUK for his helpful advice along the way, particularly the tool selection in this case. We are so lucky to have Dave and one or two other true experts on the forum, who pass on their advice freely and selflessly.


Feel free to ask any questions. I’m sure I will have missed out some significant points.

Edited by Banjoman
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I am surprised to see the heater split in a 2 months time. Wonder what's the reason for that. Maybe just a bad batch. As far as i read here, makers are really helpful if sth goes wrong. Im glad you sorted it, that's my dream machine. One day i will have space for it and there will be no excuses left not to buy it :)

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The heater split so water was in contact with the wire inside and current would have flown to earth. And yet nothing tripped. I take it you do not have an RCD. Would have been useful


I don't have an RCD. I only knew it was the element after I opened the boiler up. Perhaps I should get an RCD!

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You can get a plug-in RCD "powerbreaker" from Screwfix etc. It trips very fast @ 30mA.


(I always use one in the workshop when investigating machine electrical problems & when test-running a repaired machine. Even although the workshop has its own consumer unit with RCDs etc.on each socket)

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Serves to show there must be numerous properties out here without the RCD protection, that said installing one in a consumer unit or mounted to the side to cover the whole house in old property could set you a task with nuisance trips until you eliminate the culprits.



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I don't actually know what caused it to fail. As far as I'm aware I followed the user guide. The odd thing was that it continued to function after it had ruptured and was leaking the magnesium oxide into the brew water. I do prefer clear brew water though ;)

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It could be that the boiler wasn't filling correctly - leaving some upper part of the element overheating. So it will be worth checking with the manufacturer for mods or tests if possible to avoid a recurrence.

An ELCB (earth leakage) may have detected this problem, but otherwise the fault could continue for some while, as you found, even before an RCD detected this particular failure. There is still enough of the higher resistance path (inner hot wire) working before water contact takes place, to limit the current flow.

Water heating elements are typically only 20-50 Ohms resistance, but Vesuvius will have a value for this that you can check externally to see if all is well.

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