I just replaced yet another Mater pressurestat in my Elektra Semiautomatica - a yearly ritual - I now have 3 dead Mater stats sitting in a bag: any way to revive them - and reuse?

(Despite this stat failure design flaw in the Elektra Semiautomatica - It really is great to start using it again: I have spent the last 3 weeks using my backup machine - an E-61 group Isomac Millennium (circa 2001 machine) It did its job without giving me trouble - but it just does not make as tasty espresso as the Elektra does (nor does it steam for cappuccino as nicely).

Howard

I'm having better luck with the Jaeger stats Chris sells; the older one is on a 2 1/2 year run.

About six years back, when the sticky Mater problem first cropped up, Jack Denver, of alt.coffee fame, posted a few times that the Maters could be refurbished by submerging the membrane section in citric acid. Presumably this would take off the oxidation and restore the membrane's flexibility.

However, there was no follow up, so I don't know if its a long or short term term fix.

I was thinking about a citric acid bath: eventually I might try that when this latest Mater conks out.... and report back if it works.

My Jaeger replacement stat did not last much longer than my Mater stats did. Since it cost a lot more I switched back to Mater.

Perhaps, you use better water - I try to use a fairly fresh Brita filter pitcher now - when I had the Jaeger in - I was using distilled water a lot - for the steaming ....

Howard

There are other options
http://www.espressomachinendoctor.de/E ... 5_148.html
The Cimbali unit certainly looks impressive.
The Campini is described as being very reliable
http://www.espressomachinendoctor.de/E ... 15902.html

I suggest that periodically perhaps every descaling time or more often
remove the pstat,
(water will come out of course so do it in an appropriate environment)
with a small pipe cleaner clean the pipe
then blown some air in the pipe and as well on the pstat entry
that should extend the life of it
I have few customers trying that and seem to be working
then again
depends like you mention on the minerals presence of the water and how good or often a descaling is done

That is the one problem with the Semi. The pressurestat is under the boiler. Being submerged in water like that accelerates the failure rate. Since it is in the dead bottom of the boiler, any scale or sediment will also work its way into the capillary tube. There is just no other place to put a pressurestat on that machine without ruining the sexy look of the machine.

Hello:

Bluecold wrote: There are other options
http://www.espressomachinendoctor.de/E ... 5_148.html
The Cimbali unit certainly looks impressive.

From what I have read in a couple of Cimbali Junior related threads here at HB, the Cimbali OEM pstats that replaced the Sirais in the new Cimbali Junior models are nothing to get excited about, to say the least.

See Ken Fox's opinion in these two threads (he knows about the Cimbali Junior) ...

Problem with wandering pressurestat on Cimbali Junior DT1
and
Pressurestat surgery on Cimbali Junior

My $0.02?
I'd rule that one out.

Cheers,

CIV

The problem in the Elektra is very machine specific -- like on some home lever machines, the pstat is attached at the bottom of the boiler, with water on the membrane. Unlike those machines, it's most convenient to run the Elektra all day. This apparently puts enough extra wear on the pstat to create early failures. The problem is not device specific, but one of design, since Ceme and Jaeger pstats have also bitten the dust in the same setting.

I'm wondering if a brass mesh filter just ahead of the pstat would lengthen the service life by keeping all debris away from the membrane.

I have wondered the same thing, as the Achille has the stat in the same location. I suspect that if you descale with it in situ you may even be doing more harm than good. The water/acid just does not seem to circulate in the stat and sludge accumulates, when I received it there was also a large build up of of citric in the pipe.
I cleaned out with a syringe and citric, a half teaspoon of solids came out.