Rocket Appartamento not maintaining steam pressure

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

#1: Post by nelson »


EDIT with solution: I swapped out the control board and that fixed the issue.

My Appartamento does not seem able to hold onto pressure. I've attached a photo labelled with the parts I'll mention:

Description of what happens:

- When I turn on the machine and it starts heating up, some water escapes from the "Breaker Valve" (1 in my photo). I'm not sure if this is supposed to happen or not so I've mentioned it here.
- The machine will heat up like normal to normal pressure (around 1.1 bar).
- After pulling steam or hot water, it'll sometimes just not repressurize, other times it will repressurize and then stop, and over about 5 minutes will reduce down to 0.5 bar. Toggling the power switch or using steam or hot water will usually trigger it to repressurize.

Things I've tried:

- Hitting the resets on the safety thermostats, but they did not click. (marked 2 in my photo)
- Tapping on the pressurestat with a wooden spoon to try to jog it back, as well as adjusting it slightly up to 1.2 bar. (marked 3 in my photo).

Based on this thread: Rocket Appartamento losing steam pressure and on my testing, I'm thinking it's probably the power board, but wanted to get some second opinions here.

I am leaning towards the power board since the pressurestat appears to be working when the machine is actually heating, and the heating coils definitely seem to work, so the powerboard seems most likely to me.

What do people think? I'm out of warranty so will be trying to fix this myself.
I'm also curious if the vacuum breaker letting out some steam on startup is normal or not.


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#2: Post by catmug »

Betting that your vacuum breaker isn't sealing up. Might have some buildup on the seal. Cycling hot water would cause the plunger inside to drop, and it's probably just finding a better "seat" on the next seal when the pressure increases. That's my guess.

nelson (original poster)

#3: Post by nelson (original poster) »

Would that cause the overall pressure issues? I didn't think so since it's only releasing at the initial startup, it doesn't release anything when rebuilding pressure.


#4: Post by catmug »

Depends. If you pull enough steam/water to drop the pressure to zero, the valve will be open and the element would kick on again, build up pressure and seal.

Would be easy to tell. Watch that vacuum breaker when the issue occurs and see if it's venting steam when the machine has trouble coming up to pressure. If not, it's not the cause.

I'm far from an expert on this so please someone else hop in if you have another idea...

nelson (original poster)

#5: Post by nelson (original poster) »

Well, I went to check that this morning and now it doesn't kick in the heating elements at all, so I can't even check that.


#6: Post by DaveC »

As it's the cheapest component, I would recommend you but a replacement pressurestat, at worst you have a spare, but it sounds as it yours might be playing up. Limescale/poor water quality can cause this, or sometimes they can become sticky....possibly the microswitch is faulty...can't remember if the Appartmento uses it to drive the element directly or via an SSR.

nelson (original poster)

#7: Post by nelson (original poster) »

Hmm you think it's the pressure stat rather than the control board? I guess if I paid for the board and it ended up being the pressurestat that would be pretty bad, not as bad if I did it the other way around so that might be a good idea.

Could have been intermittently working and then finally bit the dust this morning.

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#8: Post by boublanc »

are you saying there is no heat at all?
if so check to see if you have power at the element with a volt meter.
it is normal for the vacuum breaker to release steam as the boiler reach pressure.
my first thought is the pressure-stat you can try to adjust it up/down a few times but likely the contact are burned.
years ago I experienced something similar with a isomac...
Isomac not heating up after initial warm up.

nelson (original poster)

#9: Post by nelson (original poster) »

Yeah, yesterday it would heat intermittently but as of today it stopped . Probably I'll try replacing the pressure stat.


#10: Post by JRising »

You seem to be correct about it being the powerboard. Once it gets warm its element relay no longer closes properly.

The pressostat is not "burned", it is clearly wired as a low-voltage signal switch to the powerboard.
You may want to change this, a sacrificial p-stat is much cheaper than a sacrificial powerboard.