Miele Auto Dispenser - Before there was TwinDos

[brisnat81]

Leon and I have been collecting these Supertronic Miele's which are now about 10 years old and one of them came with the Detergent Dispenser.

This device is about as big as a Kitchen Aid, and stores powder on the left and Liquid on the right. You can put a range of detergents in there, but Universal/whites is a Powder and Colours is a liquid.

The device has three connections to the machine. Two Control cables, plus a water inlet and a water outlet. When the washer calls for detergent, the water diverter valve in the washer moves to route water out of the back of the machine and into the centre mixing chamber in the dispenser. If it calls for powder, it will rotate an auger in the tub, which causes powder to fall into the mixing chamber in the middle. If it calls for liquid, it pumps it from the tank, into the mixing chamber.

The dispenser then pumps the water and detergent back into the washing machine and it re-enters via the second hole on the back.

When we got this unit, the powder dispenser worked without issues, the liquid side did not. I pulled the liquid side apart today and found it had kidney stones, there were 5 large crystals stuck in the tubes or the pump, once I dissolved those, both sides are now working correctly.

Picture 1 is what a setup would look like.
Picture 2 is with the powder dispenser removed
Picture 3 is with the top off, the motor for the auger is on the left, the detergent pump and pump to the machine is on the right.
Picture 4, is with the detergent pump and pressure switch removed
Picture 5 is the detergent pump in pieces
Picture 6 is the back of the unit
Picture 7 is the connections on the back of the washer.

The washer has capacitive touch buttons next to a bitmap Orange LCD. The solution works really well on the dryer because it has less options to choose. On the washer its a bit more fiddly because there are so many options to scroll through. It has a favorites option, so its easy enough to create preconfigured favs, so you dont need to scroll each time.

Its amazing how all this was minaturised to become twin dos. This unit uses the same type of pump as the washer to pump the detergent solution back to the washer and has a very large induction motor to drive the auger and measure the detergent.

 

[launderess]

Seem to recall one or more discussions about those Miele "AutoDos" dispensers at the time.

There Miele allowed one to use one's own choice of products including powdered detergent which always my vote.

http://ebooks.miele.com.au/miele-do...-_sep_2012/files/assets/basic-html/page6.html

 

[foraloysius]

Great find! That’s the best system for detergent dispensing. I would never consider a system that can’t deal with powdered detergent.

 

[henene4]

The reason it was pretty short lived was price, complexity and thus failure rate.

Amazing none the less.
Given Miele had LiquidDos ap decade before others took it up, one can just hope somebody else finds a way to miniaturise and cheapen the system, so we might see common automatic powder dispensing in another decade or so.

 

[brisnat81]

The device itself isn’t complex, but what it adds to the washer is, in addition to lots of water pathways, two additional controllers that you don’t see in other models, one of which seemingly has water passing through it. My assumption is that this controller is similar to what could’ve been in a commercial unit

The load detection adjusts for load size. If you start the machine empty, let it add detergent and then open the door, it’ll add more detergent when it readjusts for a full load.

The dosing controls are pretty basic, you tell the machine what type of detergent is in there and then the amount required for a normal load. When you select a cycle you can choose the level of soiling to further adjust the amount used. It then uses the weight based load sensor to select the amount of detergent to fill with and the premixed detergent enters via the dispenser to tub hose. If you’ve added regular detergents such as universal powder and colour liquid, it prevents you from using them on special cycles like silk or wool.