Help, No Water from Grouphead of Vibiemme Domobar Super

Need help with equipment usage or want to share your latest discovery?
21niko21

Postby 21niko21 » Jul 31, 2010, 2:41 pm

Hey everyone, I've had a Vibiemme super HX for about a year now and I'm having problems with it today. When I tried to flush it this morning it acted like I had a blind filter in it. It ramped up to brewing pressure and no water came out. When I turned the brew button off no water came out of the valve into the drip tray. There is water coming out of the backflow line that returns to the water reservoir.

Yesterday I removed the mushroom to check scale build-up. There is some scale build-up, but I don't think it's bad enough to cause problems. I removed the mushroom and de-scaled it today to see if that would help (I had planned on doing a full de-scale today as well). That didn't help. I added de-scale solution into the reservoir and started to de-scale, but without water going through the grouphead, etc. I'm not so sure that will help.

I referred to a few threads and the maintenance guide from 1st-line and decided to remove the OPV spring and check everything there. The OPV is very difficult (almost impossible) to turn counter-clockwise and it will not turn anymore at this point (it moved about a quarter-turn overall). So, I was unable to check the spring, etc.

Any ideas? Help is greatly appreciated. :cry:

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cafeIKE

Postby cafeIKE » Jul 31, 2010, 3:19 pm

The OPV shouldn't prevent flow to the group. If it's stuck open pressure would not build.
You could try turning the OPV in all the way, apply some food safe lube to the threads with a baby bud / q-tip.
Mark the position for easy reassembly

If you remove the mushroom cap and run the pump briefly, does water pour out the top of the group?

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erics

Postby erics » Jul 31, 2010, 4:02 pm

Your check valve is APPARENTLY stuck closed as the water you see returning to the tank is from the priming valve attached to the pump.
Image
Skål,

Eric S.
http://users.rcn.com/erics/
E-mail: erics at erols dot com

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sweaner

Postby sweaner » Jul 31, 2010, 4:02 pm

Did it work yesterday after you removed/replaced the mushroom?
Scott
LMWDP #248

www.coffeefreek.com

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cafeIKE

Postby cafeIKE » Jul 31, 2010, 4:31 pm

erics wrote:Your check valve is APPARENTLY stuck closed as the water you see returning to the tank is from the priming valve attached to the pump.
<image>

IIRC, the bypass leg valve closes @ 6-8 bar. The bypass leg valve maybe stuck open and / or the outlet is stuck closed :?:

21niko21

Postby 21niko21 » Jul 31, 2010, 4:39 pm

Water does come out of the top of the group.

cafeIKE wrote:The OPV shouldn't prevent flow to the group. If it's stuck open pressure would not build.
You could try turning the OPV in all the way, apply some food safe lube to the threads with a baby bud / q-tip.
Mark the position for easy reassembly

If you remove the mushroom cap and run the pump briefly, does water pour out the top of the group?

21niko21

Postby 21niko21 » Jul 31, 2010, 4:43 pm

I checked the mushroom yesterday after I made my shot. So, today is the first I tried to use it since then.

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erics

Postby erics » Jul 31, 2010, 5:40 pm

Just loosen the top nut on the group & then remove the entire mushroom again. Now remove the top nut and you should see a plugged screen or plugged gicleur. On the underside of the mushroom, there are four holes which feed the gicleur chamber. Something is plugged up.

Image

If you do end up removing the gicleur (probably not necessary), loosen with a 5/32 socket and then unscrew with some flex tubing that will snugly fit over the hex.
Skål,

Eric S.
http://users.rcn.com/erics/
E-mail: erics at erols dot com

21niko21

Postby 21niko21 » Jul 31, 2010, 6:24 pm

I didn't remove the gicleur, but I did remove the mushroom again to double-check that the 4 holes and the hole in the gicleur is open. I can see through all of them and water flows through all of them.

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cafeIKE

Postby cafeIKE » Jul 31, 2010, 6:50 pm

Looks like there is a stoppage in the brew path from the cam to the dispersion screw. Remove the dispersion and check that it's not plugged.

With the mushroom and the brew valve removed, water should flow from the group if poured in the top of the group or the pump is run.