Reducing pump and solenoid valve sounds

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lars6153
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Joined: Dec 05, 2016, 6:40 am

Postby lars6153 » Jan 10, 2017, 7:45 am

Hi there!
I'm working on a sound reduction for my pavoni 1el. Just changed pump from the original Ulka ex5, to a mini Ulka nme 1c. Works great, just some minor tings to add to reduce tube vibration in the reservoir. But as the pump sound was reduced, a new sound became more obvious. A click from the inlet solenoid valve, just before the pump kicks into auto fill the boiler(Well, I guess it's the valve making the click). Is it normal for the valve (sirai) to make a click? If so, are there other valve options for a "dead quiet" operation?

Séb
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Postby Séb » Jan 10, 2017, 9:46 am

I have a similar spring lever machine but plumbed so at least i don't have the noisy pump but if you can't plumb your machine :(

There is two distinct noise, the pressurestat that contract and make a distinctive click sound and the open/close selenoid action that fill the boiler when you have a plumbed machine. So in your case i guess you refer to the pressurestat click noise. Once you try a machine that get rid of the pump noise we begin to hear any subtle sound and it bugs us for sure. I am used to the click sound of my selenoid valve and it is much less then any pump. But i guess it is just like someone who get an electric car and start complaining with any wind noise, tire road noise, etc... :D

Check this thread for more infos: Noisy Sirai pressurestat

How do you like your machine?

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lars6153
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Joined: Dec 05, 2016, 6:40 am

Postby lars6153 » Jan 10, 2017, 12:04 pm

Thanks séb for feedback.
I like the machine a lot. Only thing bother me was the pump. Well besides the ugly plastic panels...
The nme pump setup is very quiet. I have added a quickmill membrane and bolted it down to a massiv junk of metal.
The click sound is from the autofill valve, for time beeing My pressostat is non functional...

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FotonDrv
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Postby FotonDrv » Jan 10, 2017, 1:18 pm

Insulate the case with high temp foam? I did it on my L1p and it made a difference.
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lars6153
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Joined: Dec 05, 2016, 6:40 am

Postby lars6153 » Jan 11, 2017, 8:14 am

FotonDrv wrote:Insulate the case with high temp foam? I did it on my L1p and it made a difference.


To insulate the case might be a good idea.

Most likely I will have to isolate the boiler from heat leakage in some kind of manner. Not sure yet, but as my current safety valve is leaking and causing excessive steam and heat, and I'm worried that the wallpaper will roll off the walls.
Remains to be seen how much heat the machine generates after the new safety valve is fitted. Maybe a new valve is all that is needed for the wallpaper to stay up...

A thermal insulation of the boiler will probably dampen sounds a bit. Since I am also planning to replace the plastic panels for wooden panels, I guess the only "dissonance" that will be heard after such renovation is the clicks.

And well, I guess I will survive, despite these clicks...

lars6153
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Joined: Dec 05, 2016, 6:40 am

Postby lars6153 » Jan 11, 2017, 9:35 am

Séb wrote:I have a similar spring lever machine but plumbed so at least i don't have the noisy pump but if you can't plumb your machine :(

There is two distinct noise, the pressurestat that contract and make a distinctive click sound and the open/close selenoid action that fill the boiler when you have a plumbed machine. So in your case i guess you refer to the pressurestat click noise. Once you try a machine that get rid of the pump noise we begin to hear any subtle sound and it bugs us for sure. I am used to the click sound of my selenoid valve and it is much less then any pump. But i guess it is just like someone who get an electric car and start complaining with any wind noise, tire road noise, etc... :D

Check this thread for more infos: Noisy Sirai pressurestat

How do you like your machine?



I read the posts about Sirai pressure switch. It made me a little unsure of how to act regarding my choice of pressure switch.

The thing is, I have already purchased a Sirai. I ordered a 20A Sirai a couple of weeks ago, however, I got home a 30A.

The 30A version will, according to the posts you referred to, be somewhat quieter than 20A, so I guess I had some luck there. On the other hand, this switch is just slightly larger/wider than desirable. However manageable...

My current ma-ter xp110 is non functional, so I do not know how much sound such a device produces.

Is a ma-ter pressure switch completely silent? Or do they produce noticeable click sounds as well?

Since I do not get past the click sounds from the selenoid valve, perhaps a more or less distinct Sirai pressure switch click is a non issue?

It might even be a nice thing to have the Sirai pressurestat clicks? If you put the machine on a timmer, you do not need to set the alarm clock. The first click, to start power up the element, a wakeup call. Then, after a nice 25-30min snooze, the Sirai clunks again "machine is ready for action, time to get up"...

And a (dumb?) question regarding the posts on Sirai/ma-ter switch; what's an ssr?

donn
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Postby donn » Jan 11, 2017, 12:20 pm

I haven't yet been able to completely follow all of this, and I'm not the expert around here either, but to the best of my knowledge ... a pressurestat (e.g., Sirai) and a solenoid valve are two different things.

The pressurestat is very much like a thermostat, it switches the electric element on and off to keep the boiler water within the desired range of temperature/pressure. The difference between a pressurestat and a thermostat is just that one responds to pressure, and the other to temperature (to the same result.) The relay-like apparatus is because of the high currents, which would burn up an ordinary switch; in principle that could be done using a solenoid driven contact, but I think not here.

The solenoid in my machine is part of the water supply mechanism. Loud clunk, the supply hose convulses, the sound of running water, loud clunk. Then the pressurestat switches on, because the pressure went down when the cold water came in. It isn't nearly as loud as the solenoid.

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Séb
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Postby Séb » Jan 11, 2017, 1:08 pm

I have the Sirai 30A pressurestat in my machine and of course can hear it click on/off and according to my friend who did replaced his 20A with the 30A,no noise reduction perceptible. The noise coming from the selenoid water inlet is louder, the click of the pressurestat is not too loud. But we are talking about noise that are much lower then a pump machine. In my case i live well with it and i think you will get used to it after a while. I have not yet read a solution that can completely remove both sound to get a full silent operation.

lars6153
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Joined: Dec 05, 2016, 6:40 am

Postby lars6153 » Jan 11, 2017, 4:49 pm

donn wrote:I haven't yet been able to completely follow all of this, and I'm not the expert around here either, but to the best of my knowledge ... a pressurestat (e.g., Sirai) and a solenoid valve are two different things.


The sure are. But they are (in my machine anyway) both made by Sirai. Good to know that you too consider the pressurestat sound being lower than the one from the solenoid valve.

So the pressurestat, to my knowledge, react on pressure changes only.

The solenoid valve is only activated when the water lever sensor is over waterline (again, to my knowledge..).

My thoughts on action taking place in a Pavoni 1EL:

The coffee making starts when the lever is lowered and water is flowing from the boiler into the chamber in the grouphead. This will cause a pressure drop (am I right?) that might engage the pressurestat. It will also cause a drop in water level, that might engage the solenoid valve. Just might...

For a one group lever machine, my boiler is huge. The pressure tank is 6,5 liter (with a content of 3,8l steaming hot water).

So I'm not so sure that the change in temperature, caused by the incoming 0,6 liter of water from the reservoir, will make a big enough pressure drop to engage the pressurestat. Nor do I know if the drop of pressure caused by letting out 0,6 liter to the grouphead chamber will effect the pressurestat.

I'm not even sure a combination of those two events will engage the pressurestat, because we might have an other factor to consider: Added pressure from the pump, filling the boiler (the must be a change (rise) in pressure, otherwise the water will not be able enter to the boiler.

So the fact that the boiler is hugh and has a big water content, and we have a lot of actions taking place (simultaneously), I guess it's impossible to separate/isolate what impact the different events will cause.

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TomC
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Postby TomC » Jan 11, 2017, 6:14 pm

I insulated the case of my old Strega with the generic (cheap) equivalent of Dynamat. It worked extremely well at cutting down noise inside the machine.

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