Siemens Surpresso - Bosch Benvenuto Replace drain valve

Introduction

If no more coffee flows through, the drain valve is often the cause. You can either replace it or change the seals.

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.

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.

Remove the seven Torx T10 screws on the rear panel.
Do not remove the back panel completely yet, the power switch is still connected.
Lift the back panel away.
Remove the two flat plugs from the inside of the power switch.

The top cover is engaged with bayonets in several places. It must first be pushed back about 1 cm and then lifted away upwards.
Grasp the powder compartment cover firmly and pull it upwards out of its hinges. Otherwise it will be in the way of the top cover.
Pull the top cover back about 1 cm. If it sticks in front, you can help a little with plastic levers.
Lift the top cover away from the top.

The side panel is attached to the front edge with three bayonets. It must therefore be lifted out upward.
Grasp the side panel firmly at the rear edge and pull it backward and upward at the same time. It should come off quite easily.
When reassembling, make sure that the bayonets on the front edge engage properly.

The side panel is attached to the front edge with three bayonets. It must therefore be lifted out upward.
Grasp the side panel firmly at the rear edge and pull it backward and upward at the same time. It should come off quite easily.
When reassembling, make sure that the bayonets on the front edge engage properly.

In order to access the drain valve, you must first loosen some cables, as well as the electronics box and the supply hose.
Remove the two Torx T10 screws at the top and bottom of the electronics box.
Pull the box out a little.

Two connectors are attached to the top. First press in the release on both connectors and pull the connectors out.
Press in the catches on the side of the two sockets and pull the sockets out of the electronics box.
No other cables need to be disconnected, lay the box on its side.
Insert translation here

Remove the Torx T20 screw of the green/yellow grounding cable on the flow heater.
Push the green/yellow grounding cable to the side.
Pull off the two flat connectors with the yellow cables on the microswitch of the gearbox.

Turn the machine around.
Remove the six Torx T10 screws that secure the gearbox to the metal partition.
Push the gearbox away from you by the black plastic pins and drive so that it comes off.
Reach into the machine from the front and find the triangular expansion tank. Turn it counterclockwise about 60° and pull it off downward

Turn the machine around again.
Now you can pull out the gearbox as far as possible. It is a bit tricky and you have to be very careful. Turn it so that you can already see the drain valve.
The drain valve is still connected to the water hose. Pull out the clamp on the water hose with a small screwdriver. This is really tedious and of course when reassembling. But with patience it works.
Then pull out the pressure hose. At its end is an O-ring it gets stuck either on the end or in the connector. Replace it - if possible - during reassembly.

Now the gearbox can be carefully lifted out and the drain valve becomes visible.
Lift out the white driver. Pay attention to the correct orientation when reassembling.

First lift away the spring at the bottom of the drain valve, you can use a small screwdriver for this.
Pull the light part of the valve down so that the four notches on the edge fit into the corresponding openings.
Lift the complete drainage valve upwards. You can use a small screwdriver to pry the upper gray part free.

The drain valve is free.
Note: this is the older version, but the newer one fits just as well.
The third picture shows the older version in disassembled condition. You can now replace the seals or the whole valve....