La San Marco 75 Export restore diary. - Page 4

Equipment doesn't work? Troubleshooting? If you're handy, members can help.
User avatar
civ

#31: Post by civ »

Hello:
RuiReis wrote: ... how the machine behaves with a presso and i don't have how to attach the probe internally...
Just as any other temperature control would, with the obvious difference being the deadband.

Sirai pressurestats are practically indestructible but quite noisy and a repair kit is what is usually done when the diaphgram stretches.
It is industrial duty equipment and the noise it can make goes unnoticed when (for example) a 5 HP compressor starts up.

Unfortunately, the price the repair kits go for is also usually high in relation to what a new unit costs but not always, it pays to shop around.
That said, I do not think the new Sirais are the same quality as they were 35 years ago and maybe a repair kit is worth it.

But I don't think you'll need a PID, I'd say a good quality temperature control with an adjustable deadband will do fine.

When I first set it up, my ca. 2000 Cimbali D/1 (on a timer in a small appartment) would wake me up and then keep me up ...
So I added a PID, which at the time was the thing to do on an HX and the clack-clack went away.

But I kept the OEM Sirai set just below 2.0 bar as a back-up safety measure just in case.
My guess is that you may be able to use your Sirai to the same end after a good refurb/clean-up.

Check this post to see how I fitted the temperature probe.
Cimbali Junior D/1 temperature probe

You basically need to find a place where you can slip in a 'T' to access the boiler at steam level with a stainless well to hold the thermocouple ie: above water level.

You'll probably be able to do this the same way I did with my D/1: at the point of exit where the tube going from the boiler to the pressurestat is located.
Just make sure it is far from the element.

BTW: a must see is Paul Pratt's page on pressurestats:
http://www.espresso-restorations.com/p-stats.html

Cheers,

CIV

RuiReis (original poster)

#32: Post by RuiReis (original poster) »

civ wrote:Hello:

Just as any other temperature control would, with the obvious difference being the deadband.

Sirai pressurestats are practically indestructible but quite noisy and a repair kit is what is usually done when the diaphgram stretches.
It is industrial duty equipment and the noise it can make goes unnoticed when (for example) a 5 HP compressor starts up.

Unfortunately, the price the repair kits go for is also usually high in relation to what a new unit costs but not always, it pays to shop around.
That said, I do not think the new Sirais are the same quality as they were 35 years ago and maybe a repair kit is worth it.

But I don't think you'll need a PID, I'd say a good quality temperature control with an adjustable deadband will do fine.

When I first set it up, my ca. 2000 Cimbali D/1 (on a timer in a small appartment) would wake me up and then keep me up ...
So I added a PID, which at the time was the thing to do on an HX and the clack-clack went away.

But I kept the OEM Sirai set just below 2.0 bar as a back-up safety measure just in case.
My guess is that you may be able to use your Sirai to the same end after a good refurb/clean-up.

Check this post to see how I fitted the temperature probe.
Cimbali Junior D/1 temperature probe

You basically need to find a place where you can slip in a 'T' to access the boiler at steam level with a stainless well to hold the thermocouple ie: above water level.

You'll probably be able to do this the same way I did with my D/1: at the point of exit where the tube going from the boiler to the pressurestat is located.
Just make sure it is far from the element.

BTW: a must see is Paul Pratt's page on pressurestats:
http://www.espresso-restorations.com/p-stats.html

Cheers,

CIV
Hi, thank you a lot for sharing your opinion, there's a lot of food for my thoughts.

Your PID installation topic is inspiring but i don't have access to such machining work, my solutions must be of the shelf ones.
I had planned to keep initially the sirai presso and later install a PID just because the deadband, the silence would be a nice bonus, but i ordered a wrong replacement kit and i can't find one suitable.

I already known Paul Pratt web page, it's bookmarked and regularly visited, i have learned a lot on it. There is also an alternative that i learned there, a Ceme pressostat... as my machine is 1000W one it wouldn't even need a SS relay...

Honestly i'm confused about the path to take... right now i'm thinking in to give a good cleaning on the membrane and see how it works... Tomorrow i might think avoid the deadband issue on an old presso and think again in the PID solution or keep it simple and install a Ceme pressostat...
Well, i have to give a good thought on it, in the end i really want to enjoy a good coffee from it and i don't want to eternally fidling on it.

Once again, thank you!!!

User avatar
civ

#33: Post by civ »

Hello:
RuiReis wrote: ... thank you a lot ...
You're welcome.
RuiReis wrote: ... don't have access to such machining work, my solutions must be of the shelf ones.
Actually (if I recall correctly), save for the well which I made and brazed myself, the rest of the pieces I added to the boiler were 'off the shelf' from a local specialised shop. As to the well, you can purchase a similar fitting from Swagelok to hold the thermocouple.

You just have to get everything in the right threads so that 'A' connects to 'B' and then to 'C' properly.
RuiReis wrote: ... planned to keep initially the sirai presso and later install a PID ...
... silence would be a nice bonus
... ordered a wrong replacement kit and i can't find one ...
Have you checked with Stefano at espressocare?
https://www.espressocare.com/search?keywords=sirai
RuiReis wrote: ... as my machine is 1000W one it wouldn't even need a SS relay...
I'd put one in anyhow and keep the stress to the contacts at a minimum.
It's not a Sirai build/spec.
RuiReis wrote: ... a good cleaning on the membrane and see how it works.
I think that's the best path.
The Sirai is most probably in good condition and if the clacking does not bother you, a repair will solve the issue.
RuiReis wrote: ... don't want to eternally fidling on it.
You have a very sturdy, well designed and time proven lever machine.
Can't get simpler than that.

Here, Patience and Prudence will be of great help throughout.
If you do things right from the start, you will never have to fiddle with it save to set the temperature. =-)

Do keep us posted with your progress.

Cheers,

CIV

RuiReis (original poster)

#34: Post by RuiReis (original poster) »

civ wrote:Hello:

You're welcome.
Hello,
Once i have to say thank you guys for spending your time giving your thoughts and helping.

Actually (if I recall correctly), save for the well which I made and brazed myself, the rest of the pieces I added to the boiler were 'off the shelf' from a local specialised shop. As to the well, you can purchase a similar fitting from Swagelok to hold the thermocouple.
It was a nice work, i wish have the skills to do one!

Have you checked with Stefano at espressocare?
https://www.espressocare.com/search?keywords=sirai
I think it's a 55mm membrane kit to the newer models such the P302-6. Mine, P302-5, have a 78mm membrane! I know this now ... :oops:

Anyway Stefano of espressocare is located in US, the customs fees would make it prohibited.
I think that's the best path.
The Sirai is most probably in good condition and if the clacking does not bother you, a repair will solve the issue.
I will give it a try!!!!

You have a very sturdy, well designed and time proven lever machine.
Can't get simpler than that.

Here, Patience and Prudence will be of great help throughout.
If you do things right from the start, you will never have to fiddle with it save to set the temperature. =-)

Do keep us posted with your progress.

Cheers,

CIV
Always good to hear such words, will do!!

Thank you.

Rui

User avatar
civ

#35: Post by civ »

Hello:
RuiReis wrote: ... a 55mm membrane kit to the newer models such the P302-6.
... P302-5, have a 78mm membrane!
I see ...
RuiReis wrote: ... espressocare is located in US, the customs fees would make it prohibited.
Portugal (that's where you are located?) is a member of the ECM.
Sirai pressurestats are made in Italy, another member of the ECM.

See https://www.sirai.com/pressostati

Obviously it makes much more sense buying the parts within the ECM as I think you would not/should not (?) have to pay any customs fees.

Their sales rep in Portugal is this one:

FLUIDOCONTROL, S.A.
Rua Eng. Ferreira Dias,938,AZ 2 4100 246 Porto | Tel. 0226199870 Fax 0226176517
E-mail: geral@fluidocontrol.pt

You could try calling or sending them an email asking about the parts you need and where to get them in Portugal/Europe.

Cheers,

CIV

RuiReis (original poster)

#36: Post by RuiReis (original poster) »

civ wrote:Hello:

I see ...


Portugal (that's where you are located?) is a member of the ECM.
Sirai pressurestats are made in Italy, another member of the ECM.

See https://www.sirai.com/pressostati

Obviously it makes much more sense buying the parts within the ECM as I think you would not/should not (?) have to pay any customs fees.

Their sales rep in Portugal is this one:

FLUIDOCONTROL, S.A.
Rua Eng. Ferreira Dias,938,AZ 2 4100 246 Porto | Tel. 0226199870 Fax 0226176517
E-mail: geral@fluidocontrol.pt

You could try calling or sending them an email asking about the parts you need and where to get them in Portugal/Europe.

Cheers,

CIV
Yes, i'm in Portugal.

You found the sales rep... I have looked in Sirai website but i couldn't find it... I contacted two local stores in the web and they didn't have any replacement kits, only new parts. I will email them!!!

Thank you a lot!!!!

Rui

chappcc

#37: Post by chappcc »

pizzaman383 wrote:I use a surface mount thermocouple on the outside of my boiler as the input for my PID and it works well. I placed it near the middle of the boiler at the mid-point of the normal water level range.
I am using a RTD PT100 sensor in a thermowell placed in the vapor phase of the boiler which works very well. Condensing steam has a higher heat transfer coefficient than water, so the temperature sensor should be a little more responsive to any transients in the boiler temperature.


pizzaman383
Supporter ♡

#38: Post by pizzaman383 »

chappcc wrote:I am using a RTD PT100 sensor in a thermowell placed in the vapor phase of the boiler which works very well. Condensing steam has a higher heat transfer coefficient than water, so the temperature sensor should be a little more responsive to any transients in the boiler temperature.
If I had an open port to use a thermowell then I would use one. Although I would probably put the sensor in the water as near to the dipper tube inlet because that is what I want controlled.
Curtis
LMWDP #551
“Taste every shot before adding milk!”

chappcc

#39: Post by chappcc » replying to pizzaman383 »

If the machine is at steady state/equilibrium, then vapor and liquid will be at the same temperature.
I used the pressure gauge port for my thermowell and teed the pressure gauge into the hot water line.

RuiReis (original poster)

#40: Post by RuiReis (original poster) »

chappcc wrote:I am using a RTD PT100 sensor in a thermowell placed in the vapor phase of the boiler which works very well. Condensing steam has a higher heat transfer coefficient than water, so the temperature sensor should be a little more responsive to any transients in the boiler temperature.

image
pizzaman383 wrote:If I had an open port to use a thermowell then I would use one. Although I would probably put the sensor in the water as near to the dipper tube inlet because that is what I want controlled.
chappcc wrote:If the machine is at steady state/equilibrium, then vapor and liquid will be at the same temperature.
I used the pressure gauge port for my thermowell and teed the pressure gauge into the hot water line.
Thank you!
Each machine have her own particularity, i'm thinking in doing it as simple as possible. It might not be an ideal one but i think it would be more sensite and better programmable than the pressostat and his associated deadband.

Rui