Rocket Appartamento low pump water flow?

Need help with equipment usage or want to share your latest discovery?
User avatar

#1: Post by jubarim »

My brother bought a Rocket Appartamento and used it for 18 months before I visited him last February in Sweden. For a few days we pulled some shots, everything was normal.

He was packing to move back to Brazil, so I tried to empty the boiler, but no water was getting out of the tap - the steam was fine, we used it everyday. I found it odd, but after trying it for a few days, somehow it worked, but the water coming out of it was grayish :x . I blamed the hard water.

We packed it in the original box and a few months later, we opened it here in Brazil. But when we powered it on, it took too long to fill the boiler. Too long... Most likely 5 minutes. I also noticed the water getting out of the e61 group had a low flow rate:

Low group flow rate
165ml in 30 seconds.

Long time to refill boiler
After 135ml of water from hot tap - it took 25s to refill boiler


User avatar
jubarim (original poster)

#2: Post by jubarim (original poster) »

I friend came today so we could try to descale the boiler - we did that with citric acid.

We isolated the boiler at first, to descale only it, due to the grayish water coming out of it. We used a hose to fully get it empty and then filled it will the solution (2 table spoons per liter). Some really small dirty come out of it, but not much.

At least the water is clear now.

But I still think the water flow is very low in the e61 group and it takes too long to refill the boiler - sometimes if evens turns off the pump and the green light blinks (I believe it's related to the pump getting hot).

Could anyone here tell me if this is supposed to be normal? Thanks a lot!!

Team HB

#3: Post by JRising »

Your flow from the head doesn't look that bad to me. Did you check the inline filter between the receiver and the pump? I can't see it well in the video, but blowing it out backward with an air compressor isn't going to hurt it. If you can blow air freely through it in both directions, it's good.

User avatar
jubarim (original poster)

#4: Post by jubarim (original poster) replying to JRising »

Hi JRising, thanks for the tips. The filter looks clean, but I will blow it with pressured air, just in case.

Yeah, you're right, checking the video, the flow seems fine.

I will also disconnect the pump water output line and measure the water flow directly from it.

User avatar
jubarim (original poster)

#5: Post by jubarim (original poster) »

The filter was clean after all.

So I disconnected the pump from the rest of the system the flow for the Ulka EX5 pump:
The measure disconnected from the rest of the machine: 210ml in 30s.

A friend has an old Fiamma with a vibratory pump, he measured it through the group: 370ml in 30s.

User avatar
jubarim (original poster)

#6: Post by jubarim (original poster) »

From what I get in EX5 charts, it should get more or less 520ml to 720ml with no pressure restriction on the output:

User avatar
jubarim (original poster)

#7: Post by jubarim (original poster) »

It turns out the issue was the pump: it was weak.

A friend borrowed a very old ulka pump he has and I replaced just as a test: the fill time got better and also the group flow.

So I ordered a new one.

In the meantime, during the tests, I broke the "deaerator" valve that's connected to the pump:


That's a really bad cost saving from Rocket... makes no sense a plastic one when the pump has a metal end.

User avatar
jubarim (original poster)

#8: Post by jubarim (original poster) »

I could not find much information about not having this valve, except the fact that some other machines doesn't (example: ECM Classika).

So we decided to leave it out until a future maintenance.

The machine is running fine without it.

User avatar
Team HB

#9: Post by Jeff »

It's a "priming valve" -- see, for example, Pump? OPV? Check Valves? Wit's end!

If I were planning on keeping the machine, I'd trade it out for a brass one if I could. I usually got my home-specific parts through Chris' Coffee service.

Edit: Looks like it may be ... tory-pumps They have the o-ring as well, if you need it.

User avatar
jubarim (original poster)

#10: Post by jubarim (original poster) replying to Jeff »

Hi Jeff, thanks for the info!

Absolutely, I already have found another place that sells the brass version, but thanks for sending one more place that sells it. I will also check the link about how it works.