One of my Creminas came to me in fine shape from a caring former owner. As such I've run it for the last 6 months or so without touching it other than to dump and fill it periodically. I finally got around to descaling with amidosulfonic acid, and ever since it makes the strangest whining noises- on the first fire up I thought my wife was listening to Sonic Youth in the other room! It does sound like well controlled feedback...

Other than the noise it works as before, but what gives? My other machine got a full strip-down and rebuild before being put into use and has never made a peep. I reckon I'll just tear it apart, clean, and replace all of the gaskets but I am still curious if any others have had this with a Cremina or any other machine.

I've not found where it's coming from; seems to be an overall vibration. Odd thing is that it happens regardless of the water level. This is on my '72 machine- maybe the older ones are more prone?

The only thing I could think of is possibly the screws that hold the boiler to the frame have loosened (especially the one at the base of the boiler) and the vibration of the water boiling in the boiler is causing the brass to vibrate against the steel frame causing a whining noise. Perhaps it is as simple as tightening a few screws.

I'd like to take a stab at this too. Although I have never experienced the problem, it seems analogous to a water heater whine. Try this to see if it's related to the electical circuit (maybe the element): When heating and it's making the noise, turn the machine off momentarily. If the noise dies instantly, then the problem is in the electrical circuit and if it continues to whine for a while when it's off, its probably related to the expansion of the steam or other parts. My theory is that if it's the boiler element....scale may have prevented or damped the vibration of it. Now that it's clean, it's resonant frequency is more audible.

starry wrote:I'd like to take a stab at this too. Although I have never experienced the problem, it seems analogous to a water heater whine. Try this to see if it's related to the electical circuit (maybe the element): When heating and it's making the noise, turn the machine off momentarily. If the noise dies instantly, then the problem is in the electrical circuit and if it continues to whine for a while when it's off, its probably related to the expansion of the steam or other parts. My theory is that if it's the boiler element....scale may have prevented or damped the vibration of it. Now that it's clean, it's resonant frequency is more audible.

You could very well be right. I had a La Pavoni Europiccola that did something similar but it was no where near as pronounced as what is being described here. But I did not pick up on the problem until one morning when I was reaching across the top of the unit my arm brushed the top of the steam tap and I got a very memorable jolt. When I tore the heating element the top coil facing the inside of the boiler had cracked and the element was exposed. I can imagine if the crack were near the bottom or closer to the metal of the boiler it would be even more pronounced. But then again the unit had begun to trip the ground fault breaker in the kitchen(duh... that should have told me something... )

It really seems it could be anybody's guess at this point. The exposed element idea is good too. There are more possibilities than I've thought of......

starry wrote:I'd like to take a stab at this too. Although I have never experienced the problem, it seems analogous to a water heater whine. Try this to see if it's related to the electical circuit (maybe the element): When heating and it's making the noise, turn the machine off momentarily. If the noise dies instantly, then the problem is in the electrical circuit and if it continues to whine for a while when it's off, its probably related to the expansion of the steam or other parts. My theory is that if it's the boiler element....scale may have prevented or damped the vibration of it. Now that it's clean, it's resonant frequency is more audible.

Good troubleshooting suggestion.

Regards
Timo

S.L. wrote:One of my Creminas came to me in fine shape from a caring former owner. ... finally got around to descaling with amidosulfonic acid, and ever since it makes the strangest whining noises...

Other than the noise it works as before, but what gives? My other machine got a full strip-down and rebuild before being put into use and has never made a peep. I reckon I'll just tear it apart, clean, and replace all of the gaskets but I am still curious if any others have had this with a Cremina or any other machine.

Were you using Durgol or the generic chemical? I found amidosulfonic acid, at least in the concentrations recommended on the Durgol label, to be very aggressive compared to CleanCaf. If you turn the element on and let the machine come to temperature, Durgol's aggressiveness increases even more. Durgol is marketed as an "instant" descaler rather than a soaking descaler. If scale had been insulating any corrosion on the element, that insulating layer may have been completely removed by the acid.

Regards
Timo