Feel free to drop me a line re the Veneziano whenever suits, but your suggestion of 'expertise' may prove to be very generous! Its only on the bench for another week though, then moving on to a new home with a friend of mine. Its a great machine, I am sure you will like it once it gets up and running. Apart from the grunt of a reasonable sized boiler, great having the easy ability to switch from tank to plumbed.

Great news re the Giotto as well!

Cheers, Chris

Mike -

It's nice that the machine is working well BUT I'm the pessimist here - I don't believe you have solved the problem. It would take an enormous amount of scale buildup to completely clog a pstat line and then I would start wondering about the validity of the boiler pressure gage. The pstat line is probably 6 mm OD whereas the line leading to the boiler pressure gage is about 1 or 1.5 mm OD.

Not that I would put any "weight" on this but I do not recall seeing ANY post here on HB where a "pstat gone wild" was attributable to scale buildup in the sensing line.

And while we're on the subject of scale - here's a quickie inspection procedure but the first place I would tackle is the pstat line and possible other lines as Nicholas suggested.
Checking an E61 Espresso Machine for Scale

That reminds me that you can also get new line for your boiler pressure gauge as well. You can ask for it at a dealer, or check with Chris' Coffee to see if the gauge line they sell will work on a Giotto. I would bet it does, but one ought to be sure. I am not confident that descaling will work overly well with such thin line.

Cheers.

--Nicholas

mb514 wrote:
Also, I have a secondary question, in the picture below, is there supposed to be a wire deriving from the part that the part that is highlighted? I am assuming this is supposed to tell the machine to shut off in the absence of water.

<image>

PS - if you didn't find out already, that second picture is suppose to have a blue wire going to your autofill controller. It's an electrical switch to detect when the water is empty in the reservoir (breaking ground with the case).

PPS - these machines can generate a lot of scale. When I bought mine, there was enough scale to almost completely insulate the HX so I couldn't get a shot above 190'. A little colon blow to the rescue and it was good to go.

Cheers
Geoff

shadowfax wrote:I am glad to hear that things are better with you. I bet with that hard water, your espresso is quite tasty.

If I may, I would suggest that one thing that will help you a lot is to pull off all the piping that you can from the machine--the steam/water tap pipes, and the pipe from the boiler to the p-stat, periodically, and take a look at them. They will be a good indication of how much scale your machine is accumulating, and you can also throw them in a bucket of strong citric acid solution to really clean them out thoroughly, something that will be instrumental in keeping your pressure controller accurate and responsive and also keeping your steaming power high.

By the way, I was curious, how do you fill the boiler when you descale? If you're using the vibratory pump, I would suggest buying yourself a spare. Those pumps aren't really designed to handle the load of filling and flushing a boiler of the size in a Giotto-class machine, and I can definitely confirm that they start acting funny after awhile. My friend has my old vibe pump machine, and it's in bad need of replacement. During a shot, the pump goes nearly silent under pressure and starts pulsing peculiarly, usually destroying the puck and causing interesting meltdowns of otherwise well-prepared shots.

Cheers
--Nicholas

Nicholas,

I don't yet have the confidence to myself take the machine apart and give it the acid bath you recommend although I do recognize this would be the best thing to do. However, having gotten a bit deeper into it than ever before, I can now imagine doing so on my own. I actually have visions of installing rotary pumps and the likes now that I have seen what is possible. We'll see.

As you suspect, I used the pump to draw detergent into the boiler from its reservoir. This afforded the advantage of leaving the superheated water and detergent together for an hour at a time, rinsing, and repeating. I will watch the action of the pump, and keep that rotary-vane bookmarked.

erics wrote:Mike -

It's nice that the machine is working well BUT I'm the pessimist here - I don't believe you have solved the problem. It would take an enormous amount of scale buildup to completely clog a pstat line and then I would start wondering about the validity of the boiler pressure gage. The pstat line is probably 6 mm OD whereas the line leading to the boiler pressure gage is about 1 or 1.5 mm OD.

Not that I would put any "weight" on this but I do not recall seeing ANY post here on HB where a "pstat gone wild" was attributable to scale buildup in the sensing line.

And while we're on the subject of scale - here's a quickie inspection procedure but the first place I would tackle is the pstat line and possible other lines as Nicholas suggested.
Checking an E61 Espresso Machine for Scale

I am not sure that the P-stat was the specific problem. I mentioned it because the pressure release was a symptom of my problem, and the local technicians focused on it every time I described the problem. I have lost a lot of faith in the local technicians.

In reality, I think the pressure release may have been due to any number of problems, which I do not fully understand as yet. One theory I have is that the line in or out of the boiler was so clogged that water was not entering or exiting at its normal pace. This may have caused a pressure increase in the absence of enough flow, resulting in the release of steam. This is purely speculative, but what I do know is that the machine behaved exactly the same after the replacement of the P-stat, which fueled by frustration. I really do not feel that the P-stat was actually at issue.

If this is any benefit in the diagnosis, in the machine's youth turning it on would generally cause the pump to kick in to fill the boiler. If left idle, the pump would do so on occasion now and then. As time went on, and especially in the past months when the other problems arose, I realize that the pump never came on when the machine was powered-up, and I do not recall any pump sound during idling afterwards. The boiler was receiving water only when the pump was actively engaged.

I cannot emphasize enough how negligent I was with this machine. This is why Nicholas's early comment about scale spurred me on so much. For about 6 years, I did no descale or backflush whatsoever. When the P-stat did appear to fail about 1 year ago, with significant fluctuations in boiler pressure during idle as a result, the examining technician was on the verge of scolding me for not cleaning it. He said it was now done, so I resumed my negligent ways. I think that effort only served as a band-aid.

Although the espresso continued to be good, the machine was clearly gradually dying. The fact that the coffee remained better than most of what I can buy at shops locally can only be a testament to ECM's build-quality of that time (or to bad coffee here). The change since the descale is absolutely phenomenal. Crema is abundant, where it was previously scarce, and I need to carefully moderate pressure when steaming milk to avoid a catastrophe, whereas I left it wide open for long periods previously.

I am certain that the problem was scale, but I remain unclear as to why. I may not have seen the last of the problems created by this, but I am at least glad to see what this machine is capable of again.

Ozark_61 wrote:PS - if you didn't find out already, that second picture is suppose to have a blue wire going to your autofill controller. It's an electrical switch to detect when the water is empty in the reservoir (breaking ground with the case).

This is what I figured. When I saw this, I imagined that one of the technicians did not bother to reconnect it. I may need to figure this stuff out for myself.

Ozark_61 wrote:PPS - these machines can generate a lot of scale. When I bought mine, there was enough scale to almost completely insulate the HX so I couldn't get a shot above 190'. A little colon blow to the rescue and it was good to go.

When it was originally bought, this machine stayed in a weekend house served by a well (already known to have higher hardness counts than municipal water) in an area known for specific hard water issues. I believe the previous owner of the house had to replace the pump in the well at one point because the mineral content in the water destroyed its components. The fact that the Giotto would sit for longish periods unused may have exacerbated the problem.

If I can find a place to do proper work on the machine, I will have it examined once more. If not, I will need to learn myself. In the meantime, frequent cleaning is the strategy.