how to set to 0.9 bar

amit

hi there, i have an old L1 , probably 4-5 years now
I'm trying to lower the pressure to 0.9 bar but without much success , i turned the screw all the way down and release the pressure about 20 times and finally after 2 hours it stabilized at 1.1bar.

any thoughts ? recommendation ?

thx

amit

Reiss Gunson

hi Amit

i am assuming you have the original 20A Sirai pressure switch?

on the top cover of the switch it will have the operating range stamped on it, from memory it is 0.5-1.4 bar

please confirm the operating range stamped on your Sirai

unless you are running fairly small doses i wouldn't really recommend going below 1.0 bar as i think you will struggle to get pre-infusion to complete

what particular problem are you trying to solve?

if you feel the machine is running too hot i expect it is because it is stuck hard in a corner, perhaps surrounded on 5 sides - if possible i would suggest relocating the machine to a spot where a greater number of sides of the machine are exposed

kind regards

reiss.

amit

one of the best espresso i had is spella coffee, i went the other day to visit the roasters ( they also use lever machine i think its called Rancilio), they calibrate their machine to 0.9 so i assumed i can try do do the same
as for my machine you are correct it is 0.5-1.4 bar

Reiss Gunson

hi amit

i dont know, but i expect that their lever will be a dipper. dippers overheat when consecutive shots are pulled because the group is mounted directly on the side of the boiler to keep the group hot, unlike a thermosiphon fed group where the heat to the group is interrupted each time a shot is pulled

for this reason they will have turned their boiler right down low to 0.9 bar

the L1 architecture is quite different as the group is not mounted on the boiler, so i would be astounded if 0.9 bar is going to yield an optimal result, even for a dark roast

as a suggestion i would start by trying to mimic the dose, pre-infusion time, extraction time and brew weight that they are using

using the same basket, or at least a similar basket might help

only after i had aligned all those other variables, would i start turning down the wick on your L1 and i wouldn't go much below 1.1 bar

if the L1 is too hot for the beans you are using the appearance of the crema is likely to be a very dark brown and it will become thin too. the brew will also taste burnt. it is only if you experience those attributes would i be turning down the boiler pressure on your L1

amit

Reiss Gunson post=13368 wrote: hi amit

i dont know, but i expect that their lever will be a dipper. dippers overheat when consecutive shots are pulled because the group is mounted directly on the side of the boiler to keep the group hot, unlike a thermosiphon fed group where the heat to the group is interrupted each time a shot is pulled

as a suggestion i would start by trying to mimic the dose and extraction time they are using

Oh, very interesting. So what bar should I set it to ? 1.3?

Thx