The valve body pressurestat is hissing... why? - Page 3

Equipment doesn't work? Troubleshooting? If you're handy, members can help.
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erics
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#21: Post by erics »

I do not own a La Nuova Era Cuadra but I have seen a few and operated them. The pressure assembly that you have (item 3 in the pic) is unique. Bezzera uses something similar (but not identical) on the BZ07/BZ10.

You expressed some concern as to whether the safety valve even worked. From the pic you showed of the disassembled safety valve (now that I look at it again), it APPEARS as though you have assembled the parts incorrectly. The o-ring you used on the vacuum breaker obviously does a good job in sealing but those o-rings are typically silicone not viton.



The assembly I bracketed in red should be turned 180 degrees but that is just a guess based on the obvious direction of flow when the valve is activated. Testing the safety valve in place takes the machine up to some high temps and corresponding pressures whereas a shop may simply apply precisely regulated air pressure.
Skål,

Eric S.
http://users.rcn.com/erics/
E-mail: erics at rcn dot com

North (original poster)
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#22: Post by North (original poster) »

Ok.

Right now I am only having the machine on as I make a coffe and then I turn it off - im looking for a replacement right now. But its still interesting to speak to you, and I know I should take it apart again and take more photos, that would be easier, but for now:

First, about the vacuum valve, what does it matter what the o-ring is made of? It is now sealing and working, but do you mean it might not hold the seal for long because its of a wrong material?


And secondly, the assembly feels right based on the flow for me, but please explain. The arrow points in the direction the preassure goes if something goes wrong - the first thing it hits is that small brass "square" that has rubber inside it (so that it seals if there is no overpreassure) and the preassure will push that down on the spring and the preassure will be released through the 90 degree "pipette" and out through the tube into the chute down to the driptray.

If it was supposed to be the other way around - with the rubber inside the "square" then that would make a seal down towards the pipette if the was preassure going in the direction of the arrow....no?

I can take more pics in the weekend.

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erics
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#23: Post by erics »

And also lol but I kinda forgot how this would fit together. Im pretty sure it is like this, but shout if it looks wrong:
. . . and the preassure will be released through the 90 degree "pipette" and out . . .
But it must also get past that second brass piece which has a shape very similar to a valve - unkess that second piece has a hole in it.

The temperature capabilities of both Silicone and Viton exceed that in all espresso machines. Silicone is a tad better in temp and is a tad softer. It is also about thrice the price. Will it last longer? - I don't know.
Skål,

Eric S.
http://users.rcn.com/erics/
E-mail: erics at rcn dot com

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slybarman
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#24: Post by slybarman »

Now that I opened my machine up and really studied the drawing Eric posted above, I realize now that the hiss I had heard was from the boiler safety valve and not the vacuum breaker valve. When I cleared the kink in the hose from the safety valve the noise subsided.

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