Cimbali boiler release valve question - it seems to pretty much constantly hiss - not a lot, but a little.

heater cycle is about 10% - 10 sec on, 100 sec off. I'm betting some of my steam is being wasted.
Boiler is insulated, though top pipes aren't yet.


here it still has it's little copper tube on (I assume to catch blow-off moisture) - it's in the front left - not talking about the big safety valve far right rear.


here is a sideways closer view, with the cap off.


Note - it sits directly on top of the boiler water level sight tune.

I've looked at the parts blowups I can find and don't know what it is, though I guess it's a vacuum breaker.

I took it apart last night and decalcified it (it was really pretty clean), but the seat is a bit etched and may need a new one. I will go replace the o-ring after I write this. I will get several and try different sizes to get around that etched part.

Other than that, machine seems to function superbly.

Kristi wrote:I've looked at the parts blowups I can find and don't know what it is, though I guess it's a vacuum breaker.

Agreed. The Cimbali Junior I evaluated had the same one, though it wasn't directly atop the boiler (no sight glass).

HB wrote:Agreed. The Cimbali Junior I evaluated had the same one, though it wasn't directly atop the boiler (no sight glass).

Is this it? "anti-depression valve"?

http://www.cafeparts.com/listCate...asp?CategoryID=118

Also apparently called "one-way valve" on the AU site.

Okay, took it (vacuum breaker valve) apart again and buffed it tons with some sort of dremmel like soft grinder brush on my drill, added new o-ring, and most of the hissing is gone. Wonder if I should get a new one and go for perfection?

Also took my sirai membrane apart to see what it was - looked like new, with a little stuff in the well under the ptfe, so cleaned that and put it all back together . I used waterproof grease on the edge under the ptfe - don't know if that was good or bad. I don't notice any change but it worked fine before. At least now I know what it looks like, and that it's clean. About .15 deadband which is fine and I think is par for those things (sirai).

About the only evidence of use/abuse I have found with this unit is a badly burned group gasket (looked like someone had taken it for a marshmallow roast)(that nonetheless came out easily)(on Cimbali you can remove the top ring with 3 bolts - then group gasket comes off easily - love it!!!) , but nothing else and little mineral deposit, and a tad of brown stuff when I caffeza'ed it.

In the meantime I have pulled the grinder apart, cleaned the doser and put the tape mod on and have it part way together. Waiting for new genuine burrs from Chris' on Tuesday.

Waiting for double needle gauge from Rutger at Cafeparts.com.

Kristi wrote:. . . added new o-ring . . . Wonder if I should get a new one and go for perfection?

I recently replaced the entire vacuum breaker on a three-month-old Cimbali Jr. with a valve of different design that one of the techs at Chris' Coffee recommended. The O-ring in the original-equipment valve was just gummy enough to make the valve stick closed about half the time. So that's another option you might consider.

Actually, whatever i did, fixed it. No hissing. Average o-ring from average hardware store.

Richard wrote:I recently replaced the entire vacuum breaker on a three-month-old Cimbali Jr. with a valve of different design that one of the techs at Chris' Coffee recommended. The O-ring in the original-equipment valve was just gummy enough to make the valve stick closed about half the time. So that's another option you might consider.

Richard-

Do you recall what breaker that was? Just curious.

FWIW, I haven't had any sticking issues on the Cimbali M32, but I have had some hissing problems. The vacuum breaker valve is well made, easy to take apart and has some "heft". From the pics, it looks to be identical. To stop the hissing (for now at least), I removed the breaker valve and "polished" the gasket (or o-ring) which had some nicks against the corresponding seat of the vacuum breaker valve. This was done with a screwdriver, twisting the bottom screw of the assembly and pushing the gasket up into the seat. These seems to smooth out some nicks and wear on the gasket.

Now, my gasket is pretty deformed to the shape of the vacuum breaker seat and I couldn't tell if it was in fact once an "o-ring" or another type gasket. Are these typically just o-rings in all vacuum breakers?

Kristi, is the Sirai in your unit the typical shrouded unit? The M32 has a "Cimbali" pstat, like the one is this picture (from Dan's Junior review):

sirai - yeah, canned pstat! rectangular box with grey 3 sided cover.

this is an early pic before I insulated the boiler.


When I removed it to clean the membrane, I unscrewed the pstat pipe up near the boiler, and unscrewed the 2 pstat clamp holder screws - easy! Flip it over and pull the 4 membrane screws. - easy!

I won't have an idea what the real pressure is until the new gauge arrives as this one was broken and even now the spring looks very funny, but it does seem to register more or less correctly. But have no idea of accuracy. I stick a probe in between the head insulation and the head to get a very rough idea of head temp and shoot for something like 200. The water will be a chunk hotter. Tastes good, whatever! Takes about 3/4 hour to warm up. At the moment I only have 1 shot/day and shut it off after I'm done.

More pics before insulation:



yeah, that gauge is still sticking out - brew pressure - waiting for new 2 needle gauge.
The water pump is also sticking out because the input cylinder was cracked - now fixed and works fine - 1995 Ulka!!!

jesawdy wrote:Do you recall what breaker that was?

This one, I think: http://www.chriscoffee.com/products/home/parts/vbreakervalve. They sent it as a replacement without me actually placing the order, so I'm going by the photograph.

Jeff, I think your M32 is a lot newer than my S/1. Since the jr grinder that came with it was dated 1995, I am assuming that the S/1 is also roughly 1995, though there is no date on it and seems to be very little use - maybe a year in a cafe, if that, and carefully cleaned/maintained until someone badly burned the group gasket and didn't realize how simple it was to fix it. Seems to be all original parts and all in top shape - like that sirai membrane! Love it.

Also, my S/1 is not "M21"


But gawd what an easy machine to use!!!!!!!!! - Same thing I raved over when I first experienced an E61 - I just stick coffee at it and it gives me back a superb straight espresso. (yes, I acknowledge there is a smattering of behind the scenes knowledge with the temp probe and a good grinder and a smattering of barista skill)