Yellow water when emptying La Pavoni Europiccola boiler

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bobsy
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#1: Post by bobsy »

Below photos of RO water I use to make coffee, and the yellow water when I empty the boiler (note: *not* through the group head) after a week of use (I usually add RO water every morning to the boiler).

Is this color caused by RO water eating through the boiler? Is my boiler screwed? Anyone else experienced this?




SOLVED: was due to RO Water being too acidic (pH 6). I added some baking soda to bring it up to 7 and no longer experience the issue.

Actually not entirely solved. Still getting a bit of a taint in the water when I let it out of the grouphead.

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homeburrero
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#2: Post by homeburrero »

bobsy wrote:Is my boiler screwed? Anyone else experienced this?
We have seen one case where the boiler's element base was literally screwed - a mild steel screw in the base of the element was rusting. See Reddish water from La Pavoni after fixing and cleaning. In that case it was fixed with a new element. I vaguely recall other cases where something steel was inadvertently dropped into the boiler and rusted. The most befuddling case involved purple water where an ink pen had been dropped into the boiler.

Your boiler looks fairly pristine, although a darker copper oxide patina might be preferable. You may be able to promote that by adding a tiny amount of bicarbonate to your RO (e.g., the rpavlis recipe). It's good that you have no blue-green, which is the usual sign of copper corrosion.
Pat
nínádiishʼnahgo gohwééh náshdlį́į́h

bobsy (original poster)
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#3: Post by bobsy (original poster) »

Thank you for your response!

The heating element is fairly new, I got it from Gabor less than 6 months ago, so I'd be very unlucky if it turned out to be my issue. Also pretty confident there is no screw or other metallic piece in the boiler that doesn't belong there.

I will try the rpavlis solution and will also empty the tank after every use.

I'm a bit nervous I've been drinking that water for months. Time to get a blood test I guess.

Sugarbeet
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#4: Post by Sugarbeet replying to bobsy »

Interesting that this is RO water. The color really reminds me of iron oxides. I have a well at my property. The water was lab tested for both bacteria and minerals. It came as safe to drink, but it contains some sort of iron ions that made it turn that color after the water was allowed to stand for a couple of days. Although the color was very faint (one needed a white tub full of water to see it) the color was exactly the same. However, the water was still clear, just yellow-ish. On your picture the water seems less transparent on the second photo?

As RO mostly removes iron ions this must be coming from the boiler itself. My guess is a piece of steel is causing it.

bobsy (original poster)
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#5: Post by bobsy (original poster) »

Yes, definitely less transparent on the second photo. I cannot find a metallic piece inside the boiler that doesn't belong here that would cause the water discoloration.

Question for y'all: looking at the picture of inside the boiler you can see some glossy reflection. Is this normal? or is this a sign some residual oil is still there?

bobsy (original poster)
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#6: Post by bobsy (original poster) »

I just did a test with tap water, the yellow color is gone. The problem is my tap water has TDS 450, and when I boil it with the Europiccola and then pour it out, TDS is at 650 (not sure if the fact the water was still warm is screwing the measurement).

If I do the measurement with the RO water, at the beginning TDS is 20, and coming out of the boiler it's 150.

I tried the RPavlis solution but the water coming out is still yellow (using RO Water).

Not sure what to do at this point.

mborkow
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#7: Post by mborkow »

If you blend tap with RO what happens? Fwiiw, this type of issue was one of the reasons why I switched away from my vintage levers as much as I loved them. If I was to get one again I'd want a steel boiler.

drH
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#8: Post by drH »

Maybe it's a long shot but is there any chance that there is contamination from something in the group head? Since water travels into the top of the group behind the piston, if there is something wrong there it could be a source.

bobsy (original poster)
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#9: Post by bobsy (original poster) replying to drH »

If I saw a difference in TDS between water coming out of the GH vs poured out from the boiler, I would agree with you. But in my situation I'm only talking about water from the boiler, so the GH is not in the equation at this point. Unless I misunderstood your question.

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homeburrero
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#10: Post by homeburrero »

bobsy wrote:If I do the measurement with the RO water, at the beginning TDS is 20, and coming out of the boiler it's 150.

I tried the RPavlis solution but the water coming out is still yellow (using RO Water).

Not sure what to do at this point.
This is a conundrum. Just to be sure, whenever using a TDS meter to make a comparison make sure you measure both at the same temperature, ideally 25 ℃ (77 ℉).

The 20 ppm reading indicates nothing is wrong with your RO. The fact that you can use rpavlis and still get the problem implies that it's not related to the lower alkalinity and pH of the RO.

If you are putting 20 ppm into the boiler, heating it, and getting 150 ppm out implies that a lot of something inside the boiler is dissolving out into the water. The fact that it is dissolving out implies that given enough flushes it should eventually disappear. I would try making up a couple gallons of that RO, spiking it with a tiny pinch of bicarbonate, mixing well, and then recording the TDS reading at room temp. Then use that water to repeatedly rinse the boiler, heating it and letting it cool. Periodically measure the TDS at room temp of the rinse water and hopefully it will eventually drop to the same TDS as the feed water (and become clearer.)

One thing that we've seen that will keep clouding a boiler's water is a ruptured element that leaks the magnesium oxide insulating filler into the water. This normally gives you a white cloudy precipitate in the water and I don't think is the case here.
Pat
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