Well, after fixing my Quick Mill Anita: no water from group head, it appears my vacuum breaker valve problem has resurfaced (at least, I think it's the vacuum breaker valve).

Symptoms:
There are symptoms similar to "Resolved: Anita boiler and steam troubles".

When first turning on the machine, the "plunger" on the vacuum breaker valve (VBV) is down, and I can see steam coming out as the machine heats up:


After I hear the water boiling and the machine comes up to temperature, the plunger comes up:



I had the machine on for 3 hours last night, and there were no problems. This morning was a different story.

When I turned on the machine, about ten minutes later I heard a big release of steam and the kitchen GFCI kicked in. There were several water puddles underneath the Anita and I could tell the inside of the machine got sprayed.

I then soaked the brass nut, teflon color, and brass plunger in vinegar for a few hours

Before:


After:


I then re-installed the assembly (added teflon tape) and turned on the machine without the cover. Unfortunately, the same thing happened again. After about 10 minutes I saw a large release of steam that shut down the machine. Luckily I wasn't standing close because the steam "blast" radius was about 8-12 inches. Unfortunately, I didn't get a video and couldn't tell where the breach happened.

Is the problem the vacuum breaker valve?

There are several styles at Chris Coffee, so which one is correct for the Anita?

Could be, but impossible to say. Best bet is pick a safe spot and turn it on, watch for the leak. The vacuum breaker might be in play, but it seems like something else might be at play. As long as there is steam pressure, it will stay shut. If something else lets go and the steam rips out, the VB valve will of course drop.

How's the safety release valve looking?

A very common issue on these QM machines is where the HX connects at the top and bottom of the boiler. These joints leak very frequently, and Chris Coffee's tech's will tell you to wrap with many layers of teflon tape and re-assemble. Had to do that to mine, upper and lower. The lower is a PITA, as the entire boiler needs to come out.

You'll usually see a trace of mineral build up where the leak is.

Good luck, but no way to be certain until you spot the leak.

I would buy the top right vacuum breaker valve and add a tee with clear hose and vent to the front panel discharge. Keeps any vapor/droplets of water from continuing to wet the inside of your machine. Some brands of machines have switched to that type, surprised code allows that so close to electrical parts.

HunkaBurninLove wrote:When I turned on the machine, about ten minutes later I heard a big release of steam...

...Unfortunately, the same thing happened again. After about 10 minutes I saw a large release of steam that shut down the machine. Luckily I wasn't standing close because the steam "blast" radius was about 8-12 inches.

nuketopia wrote:How's the safety release valve looking?

This^^

Large release of steam are rarely the vacuum breaker. My bet would be on the pressurestat sticking closed and genuinely bringing the boiler to an overpressure situation. No surprise that the sudden release of steam could/would trip the GFCI. The root cause of this is often times a build up of scale in the capillary tube between the boiler and the pressurestat, similar to the bit that clogged your gicleur. Such a blockage prevents the pressure in your boiler from acting on the pressurestat, so the heating element stays on and eventually the safety relief valve does its job, preventing catastrophic failure of the boiler.

Cheers!

- Jake

Jake_G wrote:This^^

Large release of steam are rarely the vacuum breaker. My bet would be on the pressurestat sticking closed and genuinely bringing the boiler to an overpressure situation. No surprise that the sudden release of steam could/would trip the GFCI. The root cause of this is often times a build up of scale in the capillary tube between the boiler and the pressurestat, similar to the bit that clogged your gicleur. Such a blockage prevents the pressure in your boiler from acting on the pressurestat, so the heating element stays on and eventually the safety relief valve does its job, preventing catastrophic failure of the boiler.

Thanks Jake_G and nuketopia.

I took a video with the cover off and saw that it was the safety release valve (this was 7min/10sec after turning on the cold machine. Forgive me wincing at the end):
I haven't fired up the machine for ~2 years because of this issue. And I think I did do a descale prior to having all these problems

After additional searching on HB, it appears my issues are similar to Anita boiler explosion.

Is it better to replace the pressure stat and try to clean out the capillary tube between the boiler and pressure stat?

I've had my Anita since 2006 (weekend use) so I want to know what other maintenance I should do.

It looks very easy to remove the pressurestat pipe to check for scale. It looks like you have a C.E.M.E. pressurestat, they are not too spendy to replace if the pipe is clear.

Be careful.

I would have done more than wince had I been recording that...

I have the same machine ( not sure if it's the same age) and it has a ma-ter pressurestat


Randy

I actually assumed it had a Ma-Ter, but it looks like C.E.M.E. given the yellow surround, vertical terminals and lack of a separate switch assembly...
CEME adjustable deadband vs Mater in Isomac Tea

HunkaBurninLove wrote:
I've had my Anita since 2006 (weekend use) so I want to know what other maintenance I should do.

LOL, well that was an exciting video. At least you know the safety valve is working.

On the upside these are highly, highly repairable machines. I have one of about the same age in my second home. I wound up pretty much rebuilding the thing when the lower HX fitting began dribbling. That job is a full boiler-out process. I used mine for about a decade, and it got several minor upgrades over the years, better pressure control valve, the upgraded pressure stat, a couple of pumps (which are basically consumable items) and it got a full new melamine insulation blanket as the original degraded into a mess of powder. Mine went in for warranty repair when the upper HX fitting began to leak.

So - when I did the lower one, like I said, it was a full removal of the boiler to reach it. While I was in there, I pretty much stripped everything down, then I soaked the boiler in citric acid to clean it all up (surprisingly little scale inside). I also replaced the thermal cutout, every bit of wiring that looked funky, cleaned it all up and installed a new insulation blanket, then rebuilt the brew head with all new seals and stuff. It works perfectly now and has for several years at my weekend place.

The pressure stat in these machines is on a big fat tube, not a capillary like some other machines. The switches though, can fail and stick. The back up safety devices are the thermal cutout switch, (get a new one as they have a reset button on them). The last safety device is the safety relief valve.

You can probably revive yours with a few parts, new pressure stat, new thermal cutout switch and I'd replace that insulation blanket just on general principles. There's a newer pressure control valve (aka OPV) that works better to control brew pressure.

There's a shop in Santa Cruz who fixes espresso machines. I've been there, seems like a good guy, I haven't used his services though.

The downside of all this is that the labor involved to completely refurb the machine might not be worth it. If you're willing to do the work, it won't cost much, other than a few parts and some tools, your time and a whole bunch of cuss words. All the metals are very soft and require some techniques your average tinkerer might not know, like always using two wrenches to remove things.

All in all, when these are functioning properly, they are great machines. Yours needs some work, but it can certainly make great coffee for another decade with a little love and elbow-grease cast upon it.

Chris's Coffee is the expert on these machines. They can advise parts and service methods.

nuketopia wrote: LOL, well that was an exciting video. At least you know the safety valve is working.
...
Chris's Coffee is the expert on these machines. They can advise parts and service methods.

Call it luck or stupidity, but I wanted to get the camera closer to see where the steam was venting.

Everything is leading me to check the pressure stat and the water line going to it. I thought about taking it in to that Santa Cruz repair shop, or possibly one in San Jose that I found on Yelp. But I'll be giving Chris Coffee a call to order a pstat and asking what else I should order.

Appreciate everyone's help. Feel free to provide any more comments.