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I just turned on my VII with the cup warmer removed and noticed that the vacuum breaker valve on the steam boiler is the valve that is releasing a bit of steam as the boiler heats up. For some reason I had thought that the pressure relief valve that has the plastic shield over it was supposed to do this. Which valve should be sputtering as the steam boiler heats up?
Thanks,
Mark

Vacuum breakers sometimes leak. They open and close each thermal cycle and often get clogged with scale, causing them to hiss a little even when closed.

The overpressure valve is a safety device which only opens in the rare case both your temp sensor and overtemp switch fail simultaneously (it opens at 15 bar IIRC). It should always be closed and should never leak.