It is possible that your Bacchi does not issue a shrill whistle, which it should.

If this is because your Bacchi isnt generating sufficient steam pressure because it is escaping from the body somewhere then refer to our earlier articles in this blog on how to lubricate your machine.

But if your Bacchi isn't leaking steam and isn't whistling it may be that the 'whistle' valve isn't performing as it should.

You may have read elsewhere of the steps to take in order to remove one, or more, of the valves and service them.

All I want to suggest here is that you can save yourself a lot of time and hassle by trying something less drastic first.  It doesn't always work, but it works often enough to warrant trying.

Instead of removing any valves, simply undo the 3 hex head screws on the piston assembly with a 2.5mm Allen/hex key to gain access to the piston.  The middle of the 3 valves is the one that whistles.  You will notice that it has a 'flat' side on the centre pin.  This will allow you to pinch the centre pin between your forefinger and thumb, and turn it around a few times.  Turning this centre pin in the manner described here does not affect the pressure at which the valve opens and whistles.  For this reason it is a low risk manuoerve that oftens gets your Bacchi whistling.  You will notice that this pin is sprung loaded, so jiggle it around too.  You are just trying to ensure that it is free from grit or dirt and able to open easily.

Reassemble.

This is a 5 minute job, will often get your Bacchi whistling, and doesn't run the risk of altering the pressure at which the valve is set to open.

I strongly suggest this less dramatic approach is worth a try before embarking on removal of the valves.