Steam pressure won't stop building - Rocket Appartamento

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

#1: Post by Mountains+Coffee »

Hi all,

Posting for the first time with a repair issue I'm hoping someone can help me with.

I own a Rocket Appartamento and have had it for 19 months now. The issue is that the boiler does not stop the buildup of pressure once it hits the intended 1.2 bar. The pressure will continue to build until it reaches 1.2 bar, then stop (as if it knows it's at the right pressure), then will start to build pressure again indefinitely until the machine is shut off. I've restarted the machine a few times over the week to see if it was just a weird bug, however it continues to happen. I've also tried letting pressure out of the steam wand, hot water dispenser and the vacuum valve. This lowers the pressure initially but the boiler kicks on again and the pressure builds until it's shut off.

My typical use is 1-2 espressos 7 days a week. The machine is connected to a smart plug and is turned on automatically every day at 430 am and shuts off automatically every day at 3 pm. I also have a Niche Zero connected to the smart plug and have no issues with it.

I've had multiple issues with pressure over the 19 months of owning it. The first time around it was an "electrical issue" I think may have been the controller. that was replaced by a technician, which fixed the issue. The second issue was similar to this time around where the pressure was building and not stopping, but that issues seemed to fix itself because the tech couldn't replicate the issue and I've had 9 months without additional issues until now. However, to me, three issues in 19 months sees like an absurdly high defect rate for a $1700 machine.

So a couple questions:
- Can you help me identify the issue I'm facing now and provide thoughts on how easy/difficult the repair would be to do on my own.
- Is this a normal amount of issues? Like I said, I didn't expect to have repairs needed so frequently with this level of machine.
- Assuming this is not normal, any thoughts on what to do about the machine? Having the machine is meant to be a convenience, but bringing it in for a month long repair twice a year is not convenient.

Any help is greatly appreciated. Thank you!

Zach | Cappuccinos | Denver

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#2: Post by Nunas »

I believe that machine uses a Mater pressurestat. There are two ways to wire these, direct or via a relay. If your machine is wired direct, then you need a new 'stat. If it is wired via a relay, then you still may need a new 'stat, but it could be the relay. The relay might be on its own, or part of the controller. Sorry, I can't be more definitive, but I've never seen the gut of an Appartamento.
Edit: if it is wired direct, then you will see heavy wires from the heater to the 'stat. The pressurestat will be in series with the heater.

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#3: Post by JRising »

Rather than have another thread started, please read these three pages:

Rocket Appartamento not maintaining steam pressure

If you still have questions or need help to determine which pressostat or which method of wiring you have, ask away.

Mountains+Coffee (original poster)

#4: Post by Mountains+Coffee (original poster) »

thanks, I'll take a look at it. Is this normal though? Three pressure issues in 18 months? that feels like a lot.

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#5: Post by cafeIKE »

If this ain't too political, quality isn't what it used to be.

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#6: Post by JRising » replying to cafeIKE »

You get what you pay for. Rocket does make some darn good machines... And then the affordable one to compete in the "Almost good" market.
Honda makes some perfectly good'nuf cars, they also make lawnmowers I wouldn't drive to work in.

What's great is that despite a small boiler and stupid wiring, the Appartamento can be re-wired, can have a relay added, can be all sorts of working E61 HX things, with a little work and it started off at half the price of a good machine.


#7: Post by Bluenoser »

As previous poster said.. read the previous thread.. looks like there is a cheap relay on the control board that fails due to heat..Not sure if your appartamento uses the pressureStat to control the relay, but worth investigating.

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#8: Post by homeburrero »

Bluenoser wrote:Not sure if your appartamento uses the pressureStat to control the relay, but worth investigating.
It is very easy to tell if you're willing to unplug and open the machine and look at the wires. Trace the two wires on the pressurestat and if both of them go to the controller, then you have the scheme where a 16 amp relay inside the controller switches the heater on and off, based on the continuity across the pressurestat. In this configuration the wires to the pressurestat are probably thinner than the ones that go to the element.

I'm not sure I'd call this arrangement stupid, out of respect for the Rocket engineers*. They have used it with various controllers beginning with the ECM Italy machines, and continued on some Rockets. On machines where a big Sirai pressurestat will fit they always used a wiring scheme with the pressurestat handling the frequent switching, and with the 16 amp relay inside the controller that provides power to the element circuit switching infrequently, based on the signals from the water sensors (heater shuts off whenever machine runs out of water.)

Having said that, I'm one of many who hacked my machine (an old ECM Giotto) to use an external relay. Mine started giving me controller (a Gicar) relay troubles after many years of service and the person who fixed my controller (jpboyt, Boyt Enterprises) suggested that fix.

* I think Ennio Berti, who was with Gaggia in the 70's, then ECM Italy is still with Rocket: Info on ECM Technika made in Heidelberg Germany
nínádiishʼnahgo gohwééh náshdlį́į́h

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#9: Post by JRising »

homeburrero wrote: I'm not sure I'd call this arrangement stupid, out of respect for the Rocket engineers*. They have used it with various controllers beginning with the ECM Italy machines, and continued on some Rockets.
ECM began wiring Giottos this way in the mid 2000s. They of course stopped when they stopped making Giottos and Rocket began. Rocket tried several ways of correcting the problem, including, but not limited to) going back to wiring the load on the p-stat and putting in a proper commercial P-stat on the good machines. They did so because the North American machines weren't all making it through warranty without burning out powerboards.
Unfortunately, when they introduced the Appartamento, someone must have used old electrical schematics to engineer the wiring for the new machine and didn't take into account that there would be machines exported to 120V countries. So maybe not stupid, but certainly not clever and a waste of a lot of 120V powerboards.