Our Valued Sponsor
OpinionsConsumer ReviewsGuides and How TosCoffeeGeek ReviewsResourcesForums
Espresso: Espresso Machines
Rocket Cellini Loses Pressure Fast
Donate to Coffee Kids
Coffee Kids works with farming communities around the world, improving lives. Donate today.
www.coffeekids.org
 
Not Logged in: Log In to Postlog in
New Topics updated topics   New Posts new posts   Unanswered Posts new unanswered  
Search Discussion Board search   Discussion Board FAQ faq   Signup sign up  
Discussions > Espresso > Machines > Rocket Cellini...  
view previous topic | view next topic | view all topics
Author Messages
tglodjo
Senior Member
tglodjo
Joined: 16 Oct 2012
Posts: 209
Location: Jackson, TN
Expertise: I love coffee

Espresso: La Spaziale Mini Vivaldi II
Grinder: Baratza Vario, Virtuoso
Drip: Wave, V60, Chemex, Clever
Roaster: Behmor 1600
Posted Mon Feb 25, 2013, 7:37am
Subject: Rocket Cellini Loses Pressure Fast
 

I hav owned a Rocket Cellini Premium Plus (V1, with the one manometer for boiler pressure) for about four months now. It is a fantastic machine. Recently, however, the boiler pressure has dropped to .5 while steaming. Even if I brew first and wait a little before steaming, it drops to .5 withing 15 seconds of steaming. I changed the Sirai Pressure stat to 1.1 in hopes that would help, but the same issue. In fact, I tried to up the pressure to more than 1.1, but it won't go any higher. Has anyone had this problem before? It wasn't an issue until very recently. I didn't do anything to cause this to happen (that I'm aware of). I clean and back flush regularly. The only thing that caused me to notice this was when I made several chai tea lattes back to back. The steam pressure dropped to zero (and recovered quickly), but ever since then it drops fast. Thoughts? Tips?
back to top
 View Profile Link to this post
fnacer
Senior Member


Joined: 25 Feb 2007
Posts: 465
Location: Denver
Expertise: I love coffee

Espresso: Salvatore E61, Vivaldi Mini...
Grinder: Mazzer Mini, Gaggia MDF,...
Roaster: Behmor 1600
Posted Mon Feb 25, 2013, 9:48pm
Subject: Re: Rocket Cellini Loses Pressure Fast
 

Could be a handful of things.

The first, and easiest, thing to check for is a faulty pressure relief valve. Before steaming, open the steam valve, wait until you get good steam and maybe a few drops of water, close the valve and let the pressure build up again. If steaming works as it used to at that point, then your pressure relief valve is not working and needs to be cleaned or replaced.

If the pressure continues to drop within seconds even after you bleed air from the boiler, you will want to look into the pressurestat or the water level probe.
back to top
 View Profile Link to this post
SStones
Senior Member
SStones
Joined: 24 Nov 2012
Posts: 477
Location: Canada
Expertise: Professional

Espresso: Giga 5, ECM Giotto, Rocket...
Grinder: Anfim Milano-Best
Vac Pot: No  :(
Drip: Some $30 thing from Walmart
Roaster: I buy pre-roasted.
Posted Tue Feb 26, 2013, 5:49am
Subject: Re: Rocket Cellini Loses Pressure Fast
 

If the machine weren't so new, I'd say your boiler-probe is dirty and the machine is overfilling.  When the boiler fills too deeply, your actual pocket of steam above the waterline is quite obviously smaller and 90 seconds of steaming depletes a larger percentage of a smaller volume...   I suggest checking your boiler probe.  It is possible that it is sitting too high in its sleeve and the boiler has always been overfilling since new.  It is possible that the plastic was not correctly trimmed at installation and the probe is struggling to operate at all.  If you're comfortable with taking the top off of the machine and unscrewing that probe-fitting from the boiler, you could post a picture to this forum and many of us could have an opinion about it for you.  When removing the probe fitting, be careful not to loosen the smaller nut or let the probe itself slide up or doen the sleeve.

If you want more info about this before attempting, just ask.
back to top
 View Profile Link to this post
tglodjo
Senior Member
tglodjo
Joined: 16 Oct 2012
Posts: 209
Location: Jackson, TN
Expertise: I love coffee

Espresso: La Spaziale Mini Vivaldi II
Grinder: Baratza Vario, Virtuoso
Drip: Wave, V60, Chemex, Clever
Roaster: Behmor 1600
Posted Tue Feb 26, 2013, 4:45pm
Subject: Re: Rocket Cellini Loses Pressure Fast
 

fnacer, I left the steam on for 45 sec and it dropped from 1.1 to .4, though when I turned it off, the pressure recovered quickly. Same thing happened a second time. Is this normal? I just don't remember the pressure getting so low before and I feel like it's affecting my milk steaming.

SStones, I have no idea what the boiler probe is or what exactly I need to do. I'm attaching a picture of my machine with the top off if you could give me further instructions. (and if you have a tip on how to upload a decent photo at 75kb, please share how)

tglodjo: IMG_0073b.jpg
(Click for larger image)
back to top
 View Profile Link to this post
SStones
Senior Member
SStones
Joined: 24 Nov 2012
Posts: 477
Location: Canada
Expertise: Professional

Espresso: Giga 5, ECM Giotto, Rocket...
Grinder: Anfim Milano-Best
Vac Pot: No  :(
Drip: Some $30 thing from Walmart
Roaster: I buy pre-roasted.
Posted Tue Feb 26, 2013, 6:50pm
Subject: Re: Rocket Cellini Loses Pressure Fast
 

That thin red wite is pushed on the top of your boiler fill probe.  It is just a metal rod in a plastic sleeve hanging a couple inches into your boiler.  When the boiler water touches the bottom of that metal, it grounds that red wire and your boiler-level sensor signals the powerboard to filling the boiler (Turns off the pump and fill solenoid) and starts heating it (turns on the heating element).

If you let the machine cool and be careful not to move the metal rod too much (a 16th of an inch won't make much difference) while taking the wire+connector(In rectangular plastic) off of the probe, you can then unscrew the whole probe and look at it.  If the thin plastic sleeve extends lower than the metal of the probe (Down inside the boiler) then it is not nearly sensitive enough and your boiler will overfill to random depths.
Though if your machine is brand new from your dealer, contact them about what doing this would mean for your warranty.

In your picture you can see the three things mounted through the top of your boiler.  You know the level probe now. The big brass thing is the safety relief valve, and you should just leave it be so long as it isn't a problem in any way.  That smaller valve furthest from the probe is your "Breather Valve" or Antivacuum Valve.  It is important that this be open when the machine has cooled to room temp.  What FN is suggesting is that that valve may not be opening when the machine is cold.  If it IS closed when you turn the machine on, then the pump coming on and filling the boiler when you first turn the machine on is pressurizing the boiler (The air above the waterline can't escape if that valve is closed during boilerfill).  Then the machine comes to pressure on a "False pressure" created by the pump, instead of a boiler pressure by the water being heated significantly above the boiling point.  I don't think this is your issue because you continue to get less than expected steam more than once per use.
BUT, check it anyway.  Touch that valve when the boiler is cold.  If the pin in the middle falls downward when you touch it, then it was stuck closed and is a problem.  If it was already down when cold, it is working correctly. It will slam shut after that fsssssss...Shtuup! steamy noise as the water comes to a boil.

That`s enough homework for tonight. Class dismissed.
If you do want to remove your boiler probe to look at it, and want an opinion, take a close-up picture of it lying on its side for us.  Everyone is welcome to my opinion.  :)
back to top
 View Profile Link to this post
DavecUK
Senior Member


Joined: 21 Sep 2005
Posts: 1,415
Location: UK
Expertise: I love coffee

Posted Wed Feb 27, 2013, 5:09am
Subject: Re: Rocket Cellini Loses Pressure Fast
 

tglodjo Said:

I hav owned a Rocket Cellini Premium Plus (V1, with the one manometer for boiler pressure) for about four months now. It is a fantastic machine. Recently, however, the boiler pressure has dropped to .5 while steaming. Even if I brew first and wait a little before steaming, it drops to .5 withing 15 seconds of steaming. I changed the Sirai Pressure stat to 1.1 in hopes that would help, but the same issue. In fact, I tried to up the pressure to more than 1.1, but it won't go any higher. Has anyone had this problem before? It wasn't an issue until very recently. I didn't do anything to cause this to happen (that I'm aware of). I clean and back flush regularly. The only thing that caused me to notice this was when I made several chai tea lattes back to back. The steam pressure dropped to zero (and recovered quickly), but ever since then it drops fast. Thoughts? Tips?

Posted February 25, 2013 link

Some things that caught my attention.

  1. Interesting comment about not being able to get the pressure above 1.1 The sirai stat you have takes a LOT of turns to adjust the boiler pressure, just one turn on the adjuster won't do much.
  2. The deadband of the Sirai fairly large (because it was designed for machines with larger boilers)
  3. You say it's only recently started happening.

Sirai stats are fairly reliable, but nothing in life is bulletproof....1however I have to initially make the assumption that you simply have not turned the adjuster enough to have an effect on pressure..So first try and adjust your steam boiler pressure to PEAK (very important) at around 1.3 bar. With the typical deadband of the Sirai, this may mean the boiler could run runs from as little as 0.7 to 1.3 bar.  This will give you decent steaming and brewing. The brew temps under your setup are probably on the low side, during the latter part of the shot and I doubt you need much of a cooling flush with recovery slow for back to back shots (if you did try to pull back to back shots, the second will be slightly sour. It could be lots of turns on the adjuster to raise the boiler pressure, so you have to have the machine on and FULLY warmed up to make these adjustments...this means 1 hour (minimum).

I am also assuming that this has pretty much always been happening but increasing experience with the machine has made you more aware of it. This of course may not be true and your Sirai "may" have developed a fault, unlikely, but possible.

The vacuum breaker "could" have stuck, unlikely, but more likely than the Sirai having failed. Your comment "fnacer, I left the steam on for 45 sec and it dropped from 1.1 to .4, though when I turned it off, the pressure recovered quickly. Same thing happened a second time. Is this normal? I just don't remember the pressure getting so low before and I feel like it's affecting my milk steaming." Is not clear. Do you mean:
  1. It did it twice on two totally separate occasions with the machine having been turned off in the interim
  2. It did it twice when I opened the valve a second time once it had got back up to pressure, or a second time, perhaps a lont time after, but I had not turned the machine off.

My gut instinct tells me, you don't have much experience with the machine or tech knowledge for that specific machine and that there is nothing at all wrong with it. It's simply a matter of too low a steam pressure setting and that you have simply become a little more aware of the poor steaming, because the boiler pressure too low for that machine. Now you always have to follow the guidance of your retailer (Chris Coffee I believe), they may not agree with me as regard pressure setting. That said, if it were my machine I would be setting the boiler pressure as I have said, you have to make your own choice.

You might also find it interesting to read my review of a UK Cellini done in Aug 2010, probably not much has changed apart from the addition of a commercial grade Sirai stat (which has a larger dead band than the MATER XP110, so even more important not too run at too low a pressure)

Click Here (www.bellabarista.co.uk)

What I wouldn't advocate, is buggering about with all sorts of other things you "may" not understand and introducing a fault with your machine, especially as it's still under warranty, if in doubt go back to your retailer!

P.S.Are you using it on hard water, perhaps a little scale in the take off for the boiler pressure gauge (again fairly unlikely after 4 months).
back to top
 View Profile Link to this post
tglodjo
Senior Member
tglodjo
Joined: 16 Oct 2012
Posts: 209
Location: Jackson, TN
Expertise: I love coffee

Espresso: La Spaziale Mini Vivaldi II
Grinder: Baratza Vario, Virtuoso
Drip: Wave, V60, Chemex, Clever
Roaster: Behmor 1600
Posted Thu Feb 28, 2013, 8:35am
Subject: Re: Rocket Cellini Loses Pressure Fast
 

Thank you everyone for the advice and help.

DavecUK, I think your initial though, that I am just getting more familiar with the machine and just didn't realize the low pressure to begin with, is correct. It became clear to me after making more milk-based drinks than I ever have, so I'm most willing to bet that I just didn't pay attention to the steam pressure before. Also, I was hesitant to adjust the Sirai too much, but you were right, it takes more turns than you would expect to up the pressure. In at 1.3 max now and the steam is great. One question though: why do others on this forum and elsewhere warn about increasing pressure beyond 1.1, especially is the "green zone" goes up to 1.4?

Again, I appreciate everyone's help. Thank you for putting up with a noob just getting to know his new machine!
back to top
 View Profile Link to this post
DavecUK
Senior Member


Joined: 21 Sep 2005
Posts: 1,415
Location: UK
Expertise: I love coffee

Posted Thu Feb 28, 2013, 9:30am
Subject: Re: Rocket Cellini Loses Pressure Fast
 

tglodjo Said:

One question though: why do others on this forum and elsewhere warn about increasing pressure beyond 1.1, especially is the "green zone" goes up to 1.4?

Posted February 28, 2013 link

It's the same on any forum, there are some people who restate certain bits of "knowledge" in a well meaning way, but they are wrong. I have watched in amazment over the years when if enough people say something on a forum, it seems to become accepted fact and "true". The green Zone is also a bloody laugh. The gauges are generic items rebadged for the specific manufacturers. In most cases the green zone is the green zone that the manufacturer put on the Generic gauge and it's the same for loads of machines.  So it's meaningless as a performance indicator zone for the majority of espresso machines. In a sense of showing sensible upper limits of pressure, I think most of them go to 1.5, then after that the red zone starts. The majority of safety valves on steam boilers are set to blow at around 1.8-2.02 bar. When I review test machines i usually check the temperatures and recommend to a UK retailer what the best steam pressure settings are for them to use before despatch, they will usually reset them to that or ask the manufacturer to ship to them with that pressure. Some manufacturers listen and change all their machines worldwide, others just for the specific retailer and others don't do anything.

I recommend a steam pressure based on a number of factors (including the type of pressurestat fitted and it's deadband)

  1. Whether it's dual boiler or single boiler and whether it has preheat (e.g. Expobar Brewtus II can only take a certain max steam pressure/temp in steam boiler without overheating brew boiler, because of poor preheat design. This is not the case for the Duetto, because I designed the preheat system properly).
    1.1 What may or may not cause damage to internal components or unnecessarily reduce reliability. A lot of this depends on ventilation and insulation and can change as machine design changes

  2. For HX machines, the max temperature that will allow optimum sized cooling flush coupled with decent recovery and good brew temperatures and the ability to flush and control temperature (Vertical vs Horizontal boilers have a significant effect here, because of the different heat transfer rates of steam and water, but this can be tempered by HX tube design).
    2.2 The above tempered by, what may or may not cause damage to internal components or unnecessarily reduce reliability. A lot of this depends on ventilation and insulation and can change as machine design changes

Of course every machine is different and usage patterns vary, together with individual taste. So any generic setting can often be improved on over time. A new owner normally becomes well attuned to his/her own specific machine and after a while fine tunes the steam boiler to their needs and specific machine. Overall, that's probably more than a lot of people think about when setting steam pressure and certainly there some box shifting retailers who simply ship a machine set however it comes from the factory, assuming that those are the best settings.

One day someone's going to tell me that the firmware temperature limit on a Duetto PID steam boiler is there for a reason and what those reasons are.....blah blah. The truth is, I set that limit (for various reasons) and I will make an almost certain bet that it's coded at that value into all the Gicar boxes for all manufacturers that use it, but not because they had any specific reason, just that because it came that way from Gicar, who coded the firmware that way for Izzo. So in a sense, just like the gauges <lol>

Anyway, thanks fer posting back, it good to know your problems have been solved and it may help other Cellini owners wondering whether the world will end, machine explode etc.. if they put their steam pressure above 1.1 bar. You might be surprised how many people may have been suffering in silence!
back to top
 View Profile Link to this post
view previous topic | view next topic | view all topics
Discussions > Espresso > Machines > Rocket Cellini...  
New Topics updated topics   New Posts new posts   Unanswered Posts new unanswered     Search Discussion Board search   Discussion Board FAQ faq   Signup sign up  
Not Logged in: Log In to Postlog in
Discussions Quick Jump:
Symbols: New Posts= New Posts since your last visit      No New Posts= No New Posts since last visit     Go to most recent post= Newest post
Forum Rules:
No profanity, illegal acts or personal attacks will be tolerated in these discussion boards.
No commercial posting of any nature will be tolerated; only private sales by private individuals, in the "Buy and Sell" forum.
No SEO style postings will be tolerated. SEO related posts will result in immediate ban from CoffeeGeek.
No cross posting allowed - do not post your topic to more than one forum, nor repost a topic to the same forum.
Who Can Read The Forum? Anyone can read posts in these discussion boards.
Who Can Post New Topics? Any registered CoffeeGeek member can post new topics.
Who Can Post Replies? Any registered CoffeeGeek member can post replies.
Can Photos be posted? Anyone can post photos in their new topics or replies.
Who can change or delete posts? Any CoffeeGeek member can edit their own posts. Only moderators can delete posts.
Probationary Period: If you are a new signup for CoffeeGeek, you cannot promote, endorse, criticise or otherwise post an unsolicited endorsement for any company, product or service in your first five postings.
Home Espresso Machines
Watch videos with Gail & Kat, Rocket, Jura Capresso, Saeco, Rancilio, Quick Mill, Nespresso
www.seattlecoffeegear.com
Home | Opinions | Consumer Reviews | Guides & How Tos | CoffeeGeek Reviews | Resources | Forums | Contact Us
CoffeeGeek.com, CoffeeGeek, and Coffee Geek, along with all associated content & images are copyright ©2000-2014 by Mark Prince, all rights reserved, unless otherwise indicated. Content, code, and images may not be reused without permission. Usage of this website signifies agreement with our Terms and Conditions. (0.528671979904)
Privacy Policy | Copyright Info | Terms and Conditions | CoffeeGeek Advertisers | RSS | Find us on Google+