# Lelit Bianca 9bar



## ethanweku (Jun 15, 2019)

Hi, i'm confused as to how to set the bianca to brew at 9bar, so far i have read of 2 methods:



put on the portafilter with the blind filter, paddle flow control opened fully, turn the brew lever up, make sure it's 9bar at the group head pressure gauge (ignoring the rotary pump pressure gauge)


no portafilter needed, paddle flow control closed fully, turn the brew lever up, make sure it's 9bar at the rotary pump pressure gauge


Problem is:



if i do #1, when it's actual coffee puck, the group head pressure gauge reads 9 for a bit, and then goes to 8 for a while and then goes down further with time


if i do #2, when it's actual coffee puck, the group head pressure gauge reads 8 for a bit, and then goes to 7 for a while and then goes down further with time


Any ideas?


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## Rob1 (Apr 9, 2015)

They should both do the same thing as the valve is just stopping flow completely. Sounds like the first one is the most accurate one. Pressure will drop over an extraction as flow through the puck speeds up.


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## cuprajake (Mar 30, 2020)

Adjust the machine cold

Set to 9 bar


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## DavecUK (Aug 6, 2013)

@ethanweku* I'm going to say do number 1, as this is preventing the portafilter filling with water and then water entering the brew boiler and expanding with the heat *mucking up the pressure reading.

With the group valve fully closed (unless you have some leaking in the system, the brew boiler will be full and no cold water is introduced to affect the pressure read by the gauge on the front of the machine.

http://coffeetime.wikidot.com/pressure-measuring-portafilter-rising-pressure


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## ethanweku (Jun 15, 2019)

Thanks guys for the suggestions. @DavecUK the article is so thorough, thanks!


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## psy_Gr (Sep 6, 2015)

Guys I am confused as well but my problem seems slightly different. Pump gauge reads 9 bar while group head gauge goes straight to 10,5 bar!! I am not sure whether the water expansion due to heat applies in my case because I do the test when the Bianca is totally cold (immediately after switches on).

Any ideas?


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## DavecUK (Aug 6, 2013)

@psy_Gr water expansion due to heat


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## MediumRoastSteam (Jul 7, 2015)

DavecUK said:


> @psy_Gr water expansion due to heat


 member says machine is cold Dave. I'm intrigued.


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## DavecUK (Aug 6, 2013)

The water expands significantly as soon as heating begins...so a cold machine isn't the same temperature for long, energy goes into the water from the heating element almost immediately. once the pressure reaches the 9 bar of the pump (if that's what it's set to, even a 1C rise in part of the boiler water near the heating element will raise the pressure in the sealed part of the brew circuit after the 1 way valve.


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