Gaggia Evolution sometimes running out of steam

I have a Gaggia Evolution and I have replaced the steam wand with the
Rancilio wand. Most of the time I can produce great froth by following
the often recommended procedure of beginning the frothing before the
steam ready light lights up. Appr. 30 secs after hitting the steam
switch I start steaming, most of the times it works great. But
sometimes the machine/wand starts screaming and runs out of steam. I
can tell right away when it is going to happen, the temp. does rise
very slowly in the milk right from the beginning. So: what is happening
in these instances? I feel crippled cause I'm still not quite sure how
exactly a machine of this type works internally. If I did, I'm sure my
chances of avoiding this (HATE when it happens when a friend is here
waiting for a cappuccino) would increase.
TIA

.

Relevant Pages

  • Re: Latte art with Silvia
    ... maybe it's hard to get good velvety microfoam with sylvia? ... bleed water from steam wand until only steam comes ... Put steam wand in cold pitcher and and starting the stretching ...
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  • Re: Livia temp and pressure problems
    ... you "always" have to release the false pressure by bleeding the steam wand ... pressure valve sits on top of the boiler. ... >> steam valve. ... but your steam wand trick does this as well. ...
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  • Re: Weak Steam
    ... The most obvious to me would be a milk clogged steam wand. ... tap valve. ... I think the steam and hot water tap valves are the same and ...
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  • Re: Livia temp and pressure problems
    ... A very weak, but steady, steam came from the wand. ... > closed the valve and let the machine rest. ... Given the above, your problem is with the false pressure, aka, vacuum valve, ... but your steam wand trick does this as well. ...
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  • Re: Latte art with Silvia
    ... maybe it's hard to get good velvety microfoam with sylvia? ... I have a Silvia and don't have a problem making microfoam and latte art ... bleed water from steam wand until only steam comes ...
    (alt.coffee)