Hi folks! Long time appreciator of this community. I would appreciate a couple of pointers with my machine.

My BZ07 (bought around 2012) doesn't really produce much steam out of the wand anymore - not zero, but no "buildup" of pressure. When pushing on the knob at first, almost nothing comes out. As I hold it open, the steam starts to "leak" out, with some spurts of liquid water, so that there is a stream of steam out of the wand after about 30s but nothing that is close to normal or enough to even warm milk (maybe very slowly).

Hot water knob totally fine, goes full blast with enormous amounts of steam and hot water right away.
Pulling shots still fine.
Pressure gauge reads about 1.2, operates as it did when I first got it.

Now, this has been going on for probably 2 years but after a cleaning with pipe cleaners of the wand and as far up as I could get it did not help, I kind of lost interest. Pandemic depression and all that - a whole other story. However after a deep cleaning this week which involved opening up the unit and doing a scrub of the pipes from the boiler to the wand (but not the...small device that seems to be the solenoid valve?) I decided the whole thing really needed some TLC. And I needed some help!

Also, I've been running the machine off a giant voltage converter for the last 6 years as I first got the unit in NYC where I'm from, but moved to London. The BZ07 and the grinder have been purring away fine with the 1000w converter unit - but I'm wondering if I can do a simple conversion on internals to make it 220/240v native.

I am fairly handy so am excited to get into it.... ! If you have any tips, please, I would be really grateful!

Most prosumer HX machines like this consume from 1200 to 1400 Watt. Your 1000-Watt converter is a bit small. However, that's just a comment. If it has been working for some years like this without going up in smoke, the so be it. Since this is a PIDed machine, I'm assuming that the PID display shows the boiler getting up to the proper temperature. My best guess is that your water level sensor in the boiler is corroded, and the boiler is overfilling. You should pull it out and clean it. Second guess, it would be highly unusual for the steam wand to become clogged, but the holes on the tip often do so. I'd pull the tip off and give it a good reaming. A third and also unlikely guess is that something has become clogged upstream, or maybe the control is worn out (joystick on this model?). What happens if you remove the tip and call for steam? Be careful with this, for without the restriction from the tip, lots of really how water/steam will come out.

Sorry - mistyped the power on the converter! It's a heavy 3000w unit - I remember getting a unit 2x of the 1400w power draw for peaking.

I have cleaned the steam tip (the entire wand all the way up to the wall). Pulling steam with no tip is the same, it's a bit drippy and is a whimper. I will take a video of it!

Is a water level sensor with corrosion something easily replaceable? I will do that this weekend.

lokwise wrote: Is a water level sensor with corrosion something easily replaceable? I will do that this weekend.

Yes, incredibly simple. Cleaning the corrosion off and putting the used probe back in is even easier and more cost-effective.
But I am thinking your steam valve is probably clogged.

If your boiler were terribly over-filled to the point where there was almost no steam-pocket, then you'd notice your hot water wand losing pressure within a couple seconds.

lokwise wrote:<snip>Is a water level sensor with corrosion something easily replaceable? I will do that this weekend.

Yes, it's an easy DIY. Replacement isn't normally needed. On your boiler, look for a fitting that has only one wire coming off it. That will be your sensor. First, check the connection; look to see if the wire from it to the controller is properly attached and not corroded. If the connection is good, you'll want to pull the sensor rod out. Typically, the sensor rod is held by a brass fitting that is screwed into a threaded hole on the boiler. Don't mess with that part; it will be the lower hex fitting. Above it, there should be another, smaller hex fitting that holds the sensor rod. If you loosen that fitting, you can raise or lower the probe. Measure and make a note of where it is. Even with some scale, you should be able to pull the rod out to inspect/clean as needed. You might have to unscrew the top nut if badly scaled. When you put it back, you can lower the probe somewhat if desired, to create a bit more headroom for dryer steam.
Edit: I just read John's post, which he must have sent while I was typing. I agree that the issue isn't necessarily the probe.

JRising wrote:Yes, incredibly simple. Cleaning the corrosion off and putting the used probe back in is even easier and more cost-effective.
But I am thinking your steam valve is probably clogged.

If your boiler were terribly over-filled to the point where there was almost no steam-pocket, then you'd notice your hot water wand losing pressure within a couple seconds.

Right - the hot water wand FIRES out steam and water like nobody's business.

I thought I had cleaned out the pipes from boiler to wand well - the only part I haven't pulled off and scrubbed was the solenoid(?) unit because it was not giving easily to my wrench. Will try to WD40 it and see if that's the jam too.

Use the food grade WD40 (that's a joke, don't actually ask for that at the hardware store).

In my memory a BZ07 would have a lever-type steam valve. Be sure to hold the body of the valve firmly... You can drape a rag over it to prevent surface scratches, then hold firmly with a good sized adjustable wrench while un-screwing the valve cap with a second wrench. You don't want to let the valve twist on the face of the machine and ruin the copper pipes behind the wall.

Did a full clean of everything but pulling out the boiler - no luck. I blew through the piping at sections and it's definitely the boiler where i can barely push through a stream of air (but other pipes between boiler and grouphead, hot water wand, were totally clear). I guess it's unavoidable!

That's odd; the steam fitting opens at the top of the boiler, while the hot water fitting is immersed. I'd expect the hot water outlet to scale first, or at least to some degree more than the steam outlet. Can you not remove the pipe from the top of the boiler and ream the opening to restore flow? It may not be scale that's blocking the outlet (although I can't imagine what else it might be). Perhaps it would be prudent to borrow or buy one of those cheap borescopes such as sold on Amazon, pull a boiler fitting and have a look inside.