GS3 MP paddle positions

[Jonathon Senior Member Find all posts View Profile Close Jonathon]

I recently got a new GS3 MP, but I haven't figured out the whole paddle pre-infusion thing yet.

The machine is plumbed in to a Brita C150.

There seems to be three (or four) positions (no portafilter in):

Position 1
When I move the paddle halfway, before the pump engages, which is what I understood the pre-infusion step to be, the water comes out at a trickle - about 40-50g of water in 30 seconds and the gauge shows 2-3 bar.

Position 2
When I turn the paddle a bit more, but not all the way, the pump engages and the water comes out a little bit faster than position 1, about 60g in 30 seconds and the gauge shows 10 bar.

Position 3
With the paddle all the way the water comes out at full speed (260g in 30 seconds) with a slightly different sound and the gauge shows 9 bar.

Position 4
To confuse me further, with the machine completely turned off and the paddle opened fully, about 130g comes out in 30 seconds - much more like 'line pressure' than positions 1 or 2.

Can any MP owners help me understand if this is normal?

Thanks
Jonathon

[Jonathon Senior Member Find all posts View Profile Close Jonathon]

After a bit of research I've discovered this is because the micro switch in the group is set incorrectly.

Moving it slightly, which looks like a very easy job, changes the pump from starting at the half way point, to starting further to the left, and therefore releasing water at true line pressure before the pump kicks in.

[TC . Find all posts View Profile Close TC]

After a bit of research I've discovered this is because the micro switch in the group is set incorrectly.

Moving it slightly, which looks like a very easy job, changes the pump from starting at the half way point, to starting further to the left, and therefore releasing water at true line pressure before the pump kicks in.

Yes- plenty of slack installation per favour of LM. They're getting good at slack and expensive!

We find we have to do most of them during bench test.

[Jonathon Senior Member Find all posts View Profile Close Jonathon]

It's very disappointing when you spend such a huge amount and you then need to open the group head to do something like this to get it to the state it should be in from the start.

I'll be passing on my annoyance to the retailer, a very well known Melbourne roaster (not a CS sponsor).

[trentski Senior Member Find all posts View Profile Close trentski]

The joys of finding coffeesnobs after you've made your purchase