Sound of venting steam
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An excerpt below from a recent e-mail I received
I've have some questions regarding the behaviour of the Brewtus. I hear venting sounds from the brewtus during the first few minutes of heating up but never when its fully heated up.
I removed the back panel and found water in the top thats been vented out from a valve and corrosion on the boiler. I'm attaching two pictures so you can have a look at it and perhaps understand or explain whats happening and if its a flaw or by design.
It's perfectly normal and is venting by design. The device that's doing the venting is caused the vacuum breaker valve and this closes as the steam pressure builds, with a hssss shllllr…thwp sort of sound.
The vacuum breaker valve prevents a vacuum forming in the boiler when the machine is switched off, which prevents milk or dirty milk/water being sucked up the milk wand. It also allows proper warm up when switched on without any false pressure readings and need to bleed steam from the steam wand at least once. A problem on many machines without the "Vacuum Breaker Valve"