Rocket Appartamento - Adjusting Pressurestat

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#1: Post by coolguy121 »

First of all, I enjoy machine with strong steaming performance and is quite happy with it on Rocket Appartamento.
Thinking of adjusting pressurestat to increase boil temperature a little bit. Currently machine is sitting at 1.3 bar after being on for 60 minutes, sometimes it goes as high as 1.4. Wanted to push a bit more but it has Red label on 1.5 bar as seen on pic attached.

  • I've read that adjusting pressurestat too often might cause premature failure of itself. Will adjusting this result any damage?
  • Does the 1.5 red label means that it is unsafe to push pressure near that level?

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#2: Post by stefano65 »

In a nutshell,
if you are lacking steam well...
Heat Ex will be too much but can be accommodated with cool flushing,
double boiler machine
not as bad as above,
note of course that higher is the pressure and more you are working compotes (example the safety valve) which are calibrated, based on the specif one you have to open at 1,8 or 2 bar.
Stefano Cremonesi
Stefano's Espresso Care
Repairs & sales from Oregon.

coolguy121 (original poster)

#3: Post by coolguy121 (original poster) »

Hello HB,

Hoping to learn more about boiler pressure and adjusting them.
I'd love to increase steaming performance just a bit more compared to stock setting @ 1.2-1.3 bar.
Thinking of pushing the limit and get to 1.5 bar range.

Would setting it to 1.5 bar be dangerous or damaging to the machine? Boiler pressure gauge had 1.5 bar marked as red or danger, but not sure why that is.
  • Lelit bianca has steam dedicated boiler set @ 2 bar. Is there any reason why the Rocket should be well below 1.5 bar?
  • Would it be safe to adjust up closer to 1.5 from current setting?
Thanks much for this community!

Mod note: topics combined

coolguy121 (original poster)

#4: Post by coolguy121 (original poster) »

stefano65 wrote:In a nutshell,
if you are lacking steam well...
Hey Stefano, appreciate your reply on this! In your experience, is setting pressurestat closer to 1.8 an okay thing to do?

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Team HB

#5: Post by baldheadracing »

Unlike a double boiler, your machine's boiler pressure affects the behaviour of the thermosyphon and your brew water temperature profile. A boiler that has a heat exchanger running through it is designed to operate at a target pressure, typically around 1.2 bar for a suitable brew temperature in an E-61 thermosyphon group.

Whatever the Bianca does with its steam boiler is not applicable.

Rocket Appartamento boiler temperature and flush time
-"Good quality brings happiness as you use it" - Nobuho Miya, Kamasada

Team HB

#6: Post by JRising »

It is safe to adjust your p-stat to shut off at 1.5 bar, the deadband will probably keep it in the range of 1.2 to 1.5 bar and back...

Once you've done so, you will notice how much longer your cooling flush has to be. You may also notice that it does not improve the espresso, that's up to your opinion. You can always adjust it back to a lower boiler pressure.

FWIW: I have worked on literally more than 200 Appartamentos over the last 15 years. I have found that if you can get their deadband riding from 1.4 down to 1.0 (or tighter inside those limits) that the Appartamento is easiest to work with in that range. Just my opinion.

coolguy121 (original poster)

#7: Post by coolguy121 (original poster) replying to JRising »

John, thanks for this! Glad to know. I found that I have Campini pressurestat and not sure which red screw to adjust. Do you happen to have any link to tutorial or tips? Or perhaps if its not a good idea to adjust this style? Pic is below.

Team HB

#8: Post by JRising »

Oh jeez, another Campini P-stat. I don't know if that one has the metal studs holding the body together... It is different than the ones I am used to.

While working on that machine be ALWAYS AWARE that the studs that hold the ceramic top of that p-stat in place are electrically live conductors. BE VERY CAREFUL adjusting that p-stat.

The slightly larger of the two should be the one that adjusts the pressure. I don't know that particular one, but on other Campinis they turn opposite to Mater P-Stats... Counter-clockwise is the + increase pressure. I can't be certain on yours, it doesn't have the + - markings.

coolguy121 (original poster)

#9: Post by coolguy121 (original poster) replying to JRising »

Appreciate this. I guess the only way is to adjust it and test it out! On your end, how sensitive is the screw adjustment?
Seeing some recommendation of equivalent of 5 minute dial adjustment at a time.

On your end, how much do you need to turn to reduce say from 1.2 max -> 1.0?

Team HB

#10: Post by JRising »

Between 90 degrees and 180 degrees should be a noticeable change at the gauge. Best to not go more than 180 degrees in a single adjustment just to be sure you're going the right direction and it's not an immense change.