La Pavoni - safety valve gasket to prevent dull chrome?

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Joeydiepe
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#1: Post by Joeydiepe »

Hi everyone,

I'm currently restoring an old two-switch europiccola for the first time. thanks to this forum it is going pretty wel! There is also a dutch forum like this one, but the people on home-barista are way more friendly and helpful! I like being a part of this :)

The chrome on the right side of the boiler was really dull with some blue discolouration. It starts at the safety valve and goes al the way down. Polishing helps a lot, but the blue discolouration is hard to remove. Maybe something like Blue Job would help? I was wondering if a gasket on the safety valve would prevent this in the future, but maybe this results in a looser spring which would reduce the pressure in the boiler.

Any thoughts on this?

Joël

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drgary
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#2: Post by drgary »

Is it scale that would dissolve with a diluted vinegar solution? (You don't want to overexpose chrome to acids as they can degrade it.)
Gary
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Joeydiepe (original poster)
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#3: Post by Joeydiepe (original poster) »

didn't thought about that! There are some white spots (some like drops) that could be scale. Think I try with some diluted vinegar, maybe on some paper towel and remove directly with hot (soapy) water.

What about the gasket? Of coarse I can just try it out when the rebuild is complete.
Joël

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drgary
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#4: Post by drgary »

I don't know how much difference a gasket makes. The safety valve in a two-switch La Pavoni constantly emits some steam. Scale concentrates where steam is venting. Possibly that area wasn't kept clean when scale would deposit.
Gary
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homeburrero
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#5: Post by homeburrero »

drgary wrote:The safety valve in a two-switch La Pavoni constantly emits some steam.
+1. It has a different (weaker) spring than the pStat models, and should be hissing steam at about 1 bar. You can replace the steel ball with a teflon mushroom, just be sure you get the one for the two-switch model - like this.

All steam and water coming out of that valve should be coming out of the end of the drain tube, not up by the boiler. If the drain tube mating surfaces are clean and smooth it should work that way without a gasket. Putting a gasket where you show it will have the effect of increasing the distance between the spring cap and the orifice which will tend to lower your boiler pressure a bit. Lower pressure is not a safety concern, so no harm in trying it.

Is possible that your leak is down between the fitting and the boiler. That fitting has a nut and washer on the inside of the boiler. If it is leaking there you may be able to fix it by gently tightening that fitting from the outside, but it's a little difficult if you need to get a wrench on the nut inside the boiler.
Pat
nínádiishʼnahgo gohwééh náshdlį́į́h

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drgary
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#6: Post by drgary »

After reassembly if you notice steam or water leaking from where the fitting mates with the boiler, you could try some thread sealer.
Gary
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