Isomac pressurestat, not a MATER

#1: Post by **Amorphous** » May 26th, 2014, 1:58 am

Hi,

I'm new to these forums, this is my first post although I have been lurking for a while now.

I have an Isomac Tea. I live in Australia but bought the machine from Coffee Italia, and it appears that all of their products are the European spec. My pressurestat has been sticky for a while now, but it finally got to the point where it was always sticking on so I had to pulled the machine apart to free up the diaphragm. The machine is working fine now, the pressurestat is cycling as expected but I think its probably a good idea to get a spare in case I can't free it up again next time.

My question is regarding finding a spare. All of the online parts suppliers seem to be selling Mater pressurestats as the replacement part. Mine is not a Mater, it looks like the one in this video

Does anyone know a stockist for this style of pressurestat in Australia? I'm sure the Mater functions similarly, but all of the Maters I have seen advertised are BSP threads and the one on my machine is ¼"NPT. I'm just trying to avoid using adaptors, or changing the elbow that it sits in. If I can't find a replacement, I'll have to go down the route of buying a Mater.

Thanks,
Amorphous

#2: Post by **drgary** » May 26th, 2014, 3:44 am

These screen shots of markings might help you identify it. Of course if you find something that has the same thread size as the Mater that you like better, that might work. The video doesn't show a Jaeger but they're good.

#3: Post by **DaveC** » May 26th, 2014, 2:10 pm

Get an adaptor and change over to a MATER XP110....much better in the long run.

#4: Post by **homeburrero** » May 26th, 2014, 4:15 pm

Amorphous wrote:the one on my machine is ¼"NPT.

That seems unusual - are you sure of that?
If you get a caliper and measure the width across 6 threads, you would get appx 8.0 mm on BSP and appx 8.5mm on NPT.

With a minute of searching, I ran across a replacement just like yours ( http://www.myespresso.co.uk/product.php ... tat-switch ), but if it were me I would go with a CEME or a MaTER, which should be easy to find, and I believe many suppliers sell them as replacement parts for the Isomac Tea.

#5: Post by **Beenbag** » May 26th, 2014, 7:38 pm

Mine is not a Mater, it looks like the one in this video

The PS shown in the video is a Mater !
However, if you want to change, many isomacs in Australia came fitted as standard with CEME pressurestats like this ..
http://espressocare.com/Qstore/uploads/cemepc.jpg
I also seriously doubt you have a NPT fitting, ..unless it has be modified from standard.
Aussie suppliers..
http://www.coffeeparts.com.au/misc/pressurestats
http://www.jetblackespresso.com.au/shop ... surestats/
https://www.chriscoffee.com/v/vspfiles/ ... _stats.jpg

#6: Post by **homeburrero** » May 26th, 2014, 11:15 pm

Beenbag wrote:The PS shown in the video is a Mater !

The switch looks identical to the one on the MaTER, but the body looks way different - I think is a Syncro P.E., model PE1. On Gary's screen caps you can barely make out the 'SYNCRO' and clearly see the PE1 as well as the 1 - 5 bar adjustment range.

The one sold at that myespresso.co.uk is labelled a little differently than the one in the video, but is a Syncro PE1 with the same adjustment range.

But I think that a MaTER or CEME with a lower adjustment range would be a better choice.

Be aware that the MaTER XP110 comes in both 1/4" and 1/8" and also is available in different pressure ranges, so be sure you get the one with 1/4" fitting and with the 0.5 - 1.5 bar adjustment range.

#7: Post by **cannonfodder** » May 26th, 2014, 11:24 pm

NTP thread would be quite bizarre. I had an Isomac and it was all metric thread.

You could always modify the machine a little and drop in a SIRAI. They are bulletproof, easy to find and easy to work on. The difficult part would be getting a place to mount it.

July 4th, 2014, 10:05 pm

Thanks everyone for your replies, you've all offered up a lot of useful information. My life has been extremely hectic recently so it has taken me a while to get back here.

I managed to free up the pressurestat and get the machine working again, so I'm not too keen to pull it apart just yet to confirm the thread type. I'll just trust the knowledgeable peeps on here that it is BSP and pick up a MATER as a spare in readiness of when the pressurestat locks up again. I have to say that my test of the thread was not very scientific last time I had it apart, it fitted into a NPT female fitting I had in my toolbag but I did not measure thread pitch.

Thanks again. Although this is the first time I've asked a question in these forums, I have learnt a lot over the past 18 months just from reading here.

Amorphous

#9: Post by **homeburrero** » July 5th, 2014, 2:11 am

Amorphous wrote:I have to say that my test of the thread was not very scientific last time I had it apart, it fitted into a NPT female fitting I had in my toolbag but I did not measure thread pitch.

Yes, a 1/4" male BSP may appear to fit a 1/4" female NPT. The BSP has a slightly smaller thread diameter, and the pitch difference (19 tpi on BSP, 18 tpi on NPT) might not be noticed with only a few threads engaged.