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How-to install flow restrictor?
I've lowered the boiler pressure to 1.2 bar to cope with ambient temperature, however steaming power is reduced.
I have a flow restrictor on hand, that I want to install to see if it helps.
Are there instructions on where the restrictor goes? I know it's supposed to be in the thermosyphon loop, but where exactly?
I have a flow restrictor on hand, that I want to install to see if it helps.
Are there instructions on where the restrictor goes? I know it's supposed to be in the thermosyphon loop, but where exactly?
Comments
my suggestion is you wait until next month when the enhancement kit should be shipping
the enhancement kit addresses the issue of thermal accumulation if the machine is idle for extended periods of time
but if you can't wait i will dig out an image of where it goes now - give me a moment
personally i find that it is too aggressive and you will find that it runs too cool, even if you drill the restrictor out a bit
you will find that a short flush (50-60mL) pulled before you start to prep your shot will be effective in cooling the group, without needing to muck around with the restrictor
let me know how you get on
kind regards
reiss.
there you go - i think that's fairly self explanatory
let me know if it isn't
best
reiss.
Can someone share the size (diamater and hole) of the flow restrictor?
It seems to be Francino part #FC142A but I'm trying to source one locally, for the moment.
Cheers!
Jonathan
as i wrote in my PM to you, that restrictor has a 3mm hole in it and the outside diameter is 10mm
i saw your post on HB and i must say i am somewhat intrigued that you find your L1(2012-16) runs too hot as the reason we developed the LR was to generate more heat whilst still maintaining thermal equilibrium in the system so it could handle modern light roasts; the issue was very much that the thermal equilibrium of the L1(2012-16) was great for conventional roasts but struggled with modern roasts
so i am wondering if you could post an image here of the coffee beans you are using, what origin they are, and who the roaster is?
if it were me i would start by reducing the boiler pressure to 1.0 bar as this is pressure we run on the L1/2/3 and LR with no issues whatsoever
i can tell you for free that adding a restrictor really knocks the temperature back a lot, and the chap on HB who suggested you put a restrictor in both thermosiphon pipes really was having a laugh wasn't he?
kind regards
reiss
Here's the latest blend I just finished:
I always buy beans that are within 1 week post roast date and freeze them most of the in Mason jars. I'll take 80g at a time out of the freezer and put in a airtight storage container.
This is a shot that I pulled yesterday. I had the group cooled down to 81*C (about -5*C from idle) and the shot was smooth without the ash / tobacco / burned notes I'd get at 86-87*C (starting group temp).
Dose 16g. 7 sec passive preinfusion and 5-7 sec active (until bottom of the basket is covered, few drips) shot time starts after complete release of the lever.
I will try lowering the pstat to 1.0 bar tonight. Do you want me to move the thermocouple higher on the group? My group is uber stable so my suspicions are that it' my pallet that prefers lower temperatures!
Sorry I didn't see your PM. Somehow I'm not getting any notifications when I have a new message in my inbox.
Cheers!
Jonathan
good to see you back here
thank you for posting the detail on the coffee you are using as i was wondering if you were home roasting
what you have posted looks like a modern roast to me, so i am trying to square that with your sense that you think your machine is running too hot
the group temperature reading i designed the LR(2012-16) to run with was 87C at idle - i place my temperature sensor at half the vertical distance of the group (excluding the group top) and at the 3 o'clock or 9 o'clock positions when you look down on the group from above - this will give you a higher reading than where you currently have the temperature probe which is a bit too low as it below the water jacket in the group
you write above that you reduced the group temperature by 5C - how did you achieve this temperature reduction?
the other thing i note from your description is you are not releasing the lever when the first drop falls in the cup; in the interest of standardising your process with mine i suggest you release the lever when the first drip falls as this change will make a difference to the taste in the cup; for the better if you think the coffee is getting too much heat
let me know!
reiss.
up in the middle of the group you have the water jacket being supplied by the thermosiphon and so you will measure a much more accurate temperature with a tighter data set
from memory the middle of the group neck is also the middle of the group, which can be easier to 'eyeball' - it doesnt need to be millimetre perfect in the middle, just about the middle of the vertical height of the group (excluding the group head)
reiss.
I lowered the pstat to 1.0 bar. I will move my probe, wait a few hours (my taste buds are shut right now!) and will pull a shot.
Sorry my description was wrong. I do release the lever after the first drop but that occurs while doing an active PI (holding lever at the catch point). Do you want me to grind coarser in order to get a 1st drop within the first 10 seconds of the PI at boiler pressure (lever down) and therefore pull a more "standard" lever shot?
The 5 degree is based on trials at the current probe location. Right now I'm lowering the temp by either inserting a cold PF or stalling the TS by not flushing the group after a shot and then pulling the following shot at the desired starting temp (after a short flush obviously).
If I'm having variations due on my probe location, this number could be "even" more random now!
Cheers!
if you want to be able to pin point the cause it is important to only change one element at a time
the positioning of your temperature probe is simply incorrect, so shifting that i wouldn't regard as a change; it will simply return a data set that i recognise
if it were me i would make the easiest change first, so i would leave the boiler pressure at 1.3 bar max and i would simply strip out the HB hocus from my technique and follow the very simple londinium technique
if i were using the coffee you have i would take an 18g VST or the 18-20g IMS basket and i would dose it with 18g
if you only have the stock basket we supply you should be able to dose it with 17g if you grind fine
i would grind fine, i would use the londinium distribution tool, and tamp light and level
i would mount the portafilter to the group and immediately (this point is important) pull the lever right down to the bottom of its travel in a smooth and swift motion
i would then time the number of seconds it takes for the first drip to fall in the cup; this number is an important data point
fully release the lever as soon as the first drip falls in the cup
time the length of time it takes for the shot to flow into the cup and record the time when your desired shot weight is reached and then pull the cup out from the flow
report the results here
kind regards
reiss.
IMS 18-20. 18g. WDT with Londinium distribution tool. Light even tamp. Waited for the boiler pressure to reach 3 bars. Pulled the lever smoothly in one single motion.
All 3 were not great.
The last shot (coarser grind vs the 1st 2 shots) took 18 seconds for the 1st drip but then ran way too fast (36g in 28 seconds total, with PI, so 10 seconds...)
I'm now at the 15 mark on my Niche Zero. I was at 11 for 16g with EPHQ14 basket.
Correct me if I'm wrong but with modern roasts, I'm going to get better results if the grind is finer and the puck is fully saturated during the PI phase.
On the Londinium 1, I can grind finer if I do an active preinfusion (around 3 bars from a video with a PF pressure gauge you posted a while ago).
With medium and the very few dark roasts I have pulled with my L1, I get good pulls with boiler pressure PI (1st drop around 7-10 seconds).
Thoughts?
* I have left the pstat at 1.3 bar. I will give it a try again tomorrow. Although I doubt it's the case here, I know it can be easy to mix sourness and bitterness. I'll pay a close attention.
so what temperature readings are you seeing now with the repositioned temperature probe? something around 87C?
when you say 'Waited for the boiler pressure to reach 3 bars' i presume you mean 1.3 bar?
i see you referring to using 16g with the EPHQ14 basket previously, so why not try that if that worked - dropping the dose will help to reduce the pre-infusion time when you only have boiler pressure to work with - try that at the current boiler pressure of 1.3 bar
i wouldn't worry too much about a long pre-infusion the modern roast that you are using and the advice here (for the L1(2012-16)) has been to crank the boiler pressure up as high as you can, which is circa 1.45 bar, if you aren't happy with the results at 1.3 bar
let me know how you get on
that approach is much loved on HB when using other brands of lever espresso machine to 'prove' that they can also extract modern roasts on them
to achieve this they attach thermometers to the group and then open port flush to temporarily elevate the group temperature above the equilibrium temperature for the system; this is what you are forced into with a simple dipper architecture
with a londinium it idles at the correct equilibrium temperature so there is no need to open port flush
with the current range of machines running boiler pressures of 1.0 bar you can not stall the thermosiphon - instead we elevate the pressure in the thermosiphon circuit which gives us precise temperature control for any level of roast, from traditional through medium to modern and even filter roasts
with a londinium there is no flushing and no school science equipment to stick onto your espresso machine; it maintains a perfect thermal equilibrium for any roast level with variable pre-infusion pressure
kind regards
reiss.