Reviseer de Nivona Caferomatica 770 aftapkraan

Written By: VauWeh

Comments: 4

Reviseer de Nivona Caferomatica 770 aftapkraan

Difficulty

Moderate

Steps

Time Required

No estimate

Introduction

De aftapkraan wordt zwaar belast en is een frequente bron van fouten, bijvoorbeeld als er te veel water in de lekbak terechtkomt. Deze handleiding laat zien hoe deze kan worden herzien.

Het aftapventiel is hetzelfde als bij veel apparaten van Bosch, Siemens en Melitta.

Tools

Parts

Dichtungsset Drainageventil

Step 1

Pull the power plug!
Remove all attachments such as water reservoir, coffee compartment lid, trestle drawer. Remove all coffee beans in the storage container.
Unscrew the five Torx T10 screws on the back.

Step 2

Unscrew the two Torx T10 screws on the front edge of the heat plate.
Do not remove the heat plate completely yet, its supply cables are still connected.
Lift the front edge of the heat plate and slide it forward a bit to clear the tabs on the back edge.
Put the heat plate back down, but in such a way that you can reach the screws underneath.
Unscrew the two Torx T10 screws located under the heat plate.

Step 3

Gently lift the upper side a bit and put it back down.
Push the side panel on the water tank back about 2 cm.
This may jam a bit.
Place the side panel next to the machine. Do not remove it completely yet, the cables of the switch are still connected.
Disconnect the flat plugs from the switch. Be sure to note the order of the cables for later reassembly.
Remove the side panel.

Step 4

Loosen the two insulated flat plugs with which the heat plate is connected.
Lift the top slightly upwards and loosen the nut that secures the eyelet to the green-yellow grounding cable. Remove the eyelet.
Do not remove the top yet, it is still connected with a sensor cable.

Step 5

Lift the top side slightly.
Press down the locking tab on the plug of the white sensor cable and pull off the black plug towards the front of the machine.
Press the two catches of the counterpart on the sides together and slide it out of the opening towards the back.
Now the top is free and you can remove it.

Step 6

Slide the side panel with the service door back about 2 cm and remove it.
This may jam a little.

Step 7

Reach into the machine from the front and rotate the expansion tank about 60 degrees to the right and pull downwards.
The expansion tank becomes dirty over time and can become clogged. Clean it up every now and then. It consists of two halves that can be easily separated.

Step 8

To access the drainage valve, the gear box must be removed to access the drainage valve. To do that, the way for the box must be cleared. First, the electronics must be loosened.
The electronics is attached at the top and bottom with a Torx T10 screw. Unscrew the two screws.
Pull out the electronics a few inches. Be careful not to strain the cables too much.

Step 9

Detach the pressure hose to the gear box.
Using needle-nose tweezers, pull out the clip (marked in red) that secures the pressure hose to the exhaust valve (with the round black hat, marked in yellow).
Pull out the pressure hose connector. Watch out for the O-ring, it will either get stuck in the port or in the valve. It should be replaced with a new one.

Step 10

Turn the coffee machine so that the metal partition is facing you. The gear box is secured with five Torx T10 screws that must be removed.

Step 11

The next steps are tedious. Work carefully and patiently. Make sure that no cables or hoses are getting caught on the box.
Push out the gearbox on the black plastic pin (marked green) or on the drive shaft (marked yellow) on the other side.
Pull out the box on the other side and set it aside. It will still be connected by cables and hoses, be patient.
After that the drainage valve becomes visible.

Step 12

Use a screwdriver to push back on and remove the spring at the bottom of the drain valve.
Lift out the white driver. Pay attention to the position, so he has to be used again later.
Pull the clip at the top of the valve and take out the pressure hose. Watch out for the O-ring, it gets stuck in the connection or in the valve and should be replaced with a new one.
Slide the white part of the drain valve down about 5mm.
Gently lift out the drainage valve.

Ich habe eine defekte Nivona 770 bekommen und bin gerade dabei, diverse Defekte zu beseitigen. Diese Anleitung hat jedenfalls super geklappt. Ich musste jedoch leider mehrere Kabel lösen. Deshalb empfehle ich - auch aus meinen bisherigen Erfahrungen - sämtliche zu lösenden Verbindungen farblich zu markieren und zur eigenen Sicherheit von jedem Arbeitsschritt Aufnahmen anzufertigen. Somit ist beim Zusammenbau eine fehlerfreie Verkabelung problemlos möglich. Danke nochmals.

(Google Translation:): I got a defective Nivona 770 and I am currently in the process of eliminating various defects. In any case, this tutorial worked out great. However, I unfortunately had to disconnect several cables. That's why I recommend - also from my previous experience - to color-code all connections to be loosened and to take pictures of each step of the process for your own safety. This means that error-free cabling is possible without any problems during assembly. Thanks again.

Matze -

Freut mich, wünsche weiterhin erfolgreiches Reparieren!

VauWeh -

Step 13

There are different versions of this valve. The tappet can be different, the valve stem can only be a ball, one or two seals are used. However, all valves function in the same way.
Pull the cap of the grey upper valve body. Use pliers, if it is stuck.
There are two gaskets, the flat side pointing outwards.
Newer valves have only one gasket
Plunger and downholder
Piston and spring
Replace the gaskets and reassemble the valve.