Siemens Surpresso - Bosch Benvenuto brewing unit maintenance

Written By: VauWeh

Comments: 19

Siemens Surpresso - Bosch Benvenuto brewing unit maintenance

Difficulty

Moderate

Steps

Time Required

No estimate

Introduction

The gaskets of the brewing unit are heavily used and should be replaced from time to time.

This brewing unit is identical to units of other brands, e.g. Nivona, Bosch, Melitta. Note: the pictures show the newer version of the brewing unit with the large release lever. There are hardly any differences for the repair.

Tools

TR10 Torx Security Screwdriver

Parts

Dichtungssatz Brühgruppe

Step 1

Never forget: Pull the power plug!
Remove all attachments such as water reservoir, coffee compartment lid, trester drawer.
Remove all coffee beans from the bean hopper.
Open the side flap.

Step 2

Loosen the three rubber caps on the brew group.
Using a strong flat-blade screwdriver, adjust the three plastic slots underneath so that the "unlocked" position is indicated.
Note: with the newer version of the brew group, only one lever needs to be flipped.
Pull out the brew group. If it is stuck, pull firmly and evenly, but with feeling, preferably at the bottom right.

Step 3

Remove the brewing unit from the device.

Step 4

Take off the cap covering the screwhole in one corner. The cap ensures a better fit of the brewing unit.
Note: some versions of the brewing unit do not have this cap.

Step 5

Remove the single black Torx T10 screw fixing the opening handle.
Using a certain amount of force pull the opening handle out of the guidance near the red button.
Rotate the handle 90 degrees counterclockwise, then lift it off.

Step 6

Unclip the upper protection panel, then remove it by lifting it up.

Step 7

Remove six Torx T15 screws holding together the brewing unit. The screwholes are rather deep.
Lift the upper half of the brewing unit up.

Step 8

The inside of the brewing unit ist exposed. You can see:
The upper piston and its gasket.
The funnel for the coffee grounds
The lower piston.
The hold-down clamp

Hi, Thank you for your howto. It is very detailed and helpful.

There is another seal in the lower piston. it seems to be a lip seal.

I searched and couldn't find a remplacement for that. do you know where I can buy it?

Many thanks

Iklef Mallem -

Do you mean this one? See the comments in step 9.

VauWeh -

Step 9

Remove the funnel.
Rotate the lower piston counterclockwise and lift it off.
Lift off the upper piston. There ist still a hose connecting the piston to the coffee outlet. In top there ist also the downholder of the brewing unit.
Sometimes this downholder ist torn and the coffee leaks out of the brewing unit and does not fill your cup. Inspect the downholder for cracks. You can fix this using a special repair kit.

Anyone seen the repairkit somewhere?

Hugo van der Kooij - 04/10/20

Repairkit and Part

VauWeh - 04/10/20

we have taken the piston out to replace the gasket, and noticed that 2 of the 3 return springs within the housing surrounding the piston are broken and offset. can we buy these springs as spare parts anywhere? many thanks

Hannah -

Until now I didn't find these springs as spare parts. You already have the brewing unit, so I would buy a used one (e.g. from ebay ) and take the parts from it. The brewing unit could be from an older Melitta, Bosch, Siemens or Nivona.

VauWeh -

Was ist dieser Niederhalter? Wo kann dieses Teil reißen, kannst du mir kurz einen Hinweis geben. Bin mir unsicher auf welches Teil zu verweist. Evtl. könnte man es im Bild farblich markieren. Danke!

kapott -

Habs jetzt in Bild 5 grün markiert. Es ist wie eine Brücke über dem oberen Kolben. Er trägt auf der Unterseite eine kleine Gummidichtung (kann auch kaputt gehen), die verhindert, dass der Kaffee oben über dem Kolben rausfließt (sondern zum Kaffeeauslauf nach vorne), wenn der Kolben ganz oben ist. Der Riss kommt recht häufig vor; er ist ziemlich unauffällig, du erkennst ihn, wenn du versuchst den Niederhalter zu verbiegen. Eine mögliche Quelle habe ich ja oben am 3.Okt.2020 angegeben.

VauWeh - 19/02/24

Step 10

Remove the hose connecting the upper piston and the coffee outlet.
Remove the upper piston.
Remove the Torx T20 screw from the screen of the upper piston.
Take off the cover of the gasket and the gasket.
Replace the gaskets of the upper piston, the coffee outlet and water connector.
The lip of the piston gasket must point towards the pressure, i.e. downwards.
Clean thoroughly all parts. Use food-proof silicone grease to lubricate the gaskets.

I have no coffee/water coming tru the outlet of the upper piston, i can see water runs into the piston chamber but nothing goes tru. I have changed the drain valve without luck - Any clue of what my problem could be?

Christian - 09/04/21

Check for a tiny crack in the downholder .

VauWeh - 09/04/21

Just checked the downholder, it looks fin also without cracks.

next step?

Christian - 11/04/21

Well, are you sure that the issue is really with the brewing unit? I would ask someone if they could borrow a brewing unit for testing. As many machines are produced by the same factory and are equally designed (Eugster in Portugal) brewing units from Nivona, Bosch and Melitta will also fit.

VauWeh - 11/04/21

Das Sieb am oberen Kolben ist eine Torx T10 Schraube.

Jarling -

Step 11

The crema-valve is located in the interior of the upper piston. It is fixed by two Torx T10 screws.
Remove both screws. Lift off the valve. Inspect it and clean it.
Note: there is another gasket on the shaft of the lower piston. Replacing it is difficult.
Lubricate all sliding parts with food-proof silicone grease. Verify the smooth operating of the brewing unit.

Nice article, I’ve renewed the lip seal in the brewing unit but I still don’t get even a drop of coffee in the cup, it all goes in the drip tray.

I have dismantled the brewing unit complete and suspect the lower piston seal to be the problem as it doesn’t provide any “resistance” or tight fit.

You say; “replacing is difficult”, but no instructions. Could you please provide a link?

Many thanks in advance.

Kim Conrad Jorgensen -

You can buy the O-ring here. There is a cover glued over it. You have to break it out and reattach it later with a special food-safe adhesive. It's tricky and often doesn't work. I avoid this repair and try to get a used brew chamber. Are you sure the downholder and its seal is ok?

VauWeh -

And: Did you have a look to the drainage valve?

VauWeh -

Hi,

Thanks for the instructions.

There was a round spring that fell of when I dismantle, do you know where this should be?

I think it is the gray circle in step 6 picture, down to the left (8th o´clock) from the yellow circle?

Claes K. -

Yes, there is a helix spring. Just put it in.

VauWeh -

Hello. I managed to replace the o-ring for the piston, I mean taking out and installing the new one, using a tool from this kit: YT-08429 .

Ursan Andrei -