Post By Nordic
Post By Lyrebird
VBM Domobar Super Lever questions
im a long time reader and 1st time poster.
I hoping to get some feedback and information of the forum experts.
We recently got our hands on a 2nd hd. VBM Domobar Super to replace our Breville EM6910.
We already can taste the difference in coffee extraction but the machine appears to have some little issues i would like to address.
1. I have noticed that the brew pressure gauge wont go all the way done to Zero, even there is no boiler pressure the gauge shows min. 3 bar
When pulling a shot it goes to around 13-14bar. Same stays for the Steam Gauge, it does not go down to Zero
2. I've also noticed that the valve on top of the boiler (i believe vacuum relief valve its called) will slightly blow off and leak a little bit steam or dripping water for a second or 2 when the machines is fully heated up after its turned on.
3. Is it recommended to bring the Machine to an Service Agent to get it checked out? If so, are there any recommendation preferable in the SE of Melbourne which can do the service on VBM machines. What would be a basic service charge for one of those Machines.
Appreciate every feedback.
Noticed there haven't been any replies as yet to your queries so I'd like to get this thread started for you. By the way welcome to CoffeeSnobs!
If you don't have it already, here's a link to a manual that may make interesting reading-
The manual states that the brew gauge doesn't supply any useful reading other than when actually brewing when you should see 9 to 9.5 bar. This number is widely quoted as the sweet spot for pressure at the portafilter which is set by service people using a Scace device. Previously on this forum someone involved with servicing has said that the brew gauge on the machine needs to read between 0.75 to 1.5 bar above this to achieve the correct pressure at the portafilter when brewing so around 10 to 10.5 bar. Yours at 13-14 bar sounds too high so the OPV needs adjusting to drop this unless the gauge is out of calibration by the 3 bar at rest you quoted. A good service will check/fix this and check that temperature is at the correct setting also.
Originally Posted by Nordic
DIY Ref: https://www.home-barista.com/repairs...ure-t4152.html
Its possible that the Gauge not going back to zero when the system is depressurised is caused by some scale having made its way into the capillary line to the gauge? Others may be able to comment on this to clarify.
See also - http://coffeesnobs.com.au/brewing-eq...uge-query.html
This sounds like it may be normal but others more familiar with HX machines may like to comment.
Originally Posted by Nordic
Read comment by TC in this thread re: water level sensing and using too pure (no mineral content) water leading to overfilling (page 12 of manual) -
Vacuum Breaker - Coffeetime
The Pressure Relief Valve - Coffeetime
Hope this gets the ball rolling for you and encourage others familiar with this machine to chip in.
Last edited by CafeLotta; 12th February 2018 at 04:55 PM.
Reason: add links
Thanks... Much appreciated. I have decided to give it for general service and check over to one of the sponsors (Anthony from Casaespresso in Brighton) I will keep you posted on the outcome. This way we can add some information for future searches in.
Late to the party, but I recently bought a second hand VBM with the same problem.
I pulled it apart and couldn't see any damage so I assumed it was caused by the gear arc attached to the Bourdon tube (the active element of the pressure gauge) jumping a cog.
The internals didn't allow me to reset the gear so I applied the quick and dirty fix:
Remove the face plate. (It simply prises off).
Gently pull the gauge needle off the spindle.
Place the needle so it is pointing directly at the stop pin, press it on to the spindle then jump it over the stop pin so it sits against it at rest.
I'd post pics but I am a newbie.