Frans Goddijn post=17110 wrote: [quote=Emil Rønnow post=17109]To sum up my current concern is the message “Check Expvalve”
I believe Reiss explained this in one of the messages about this phenomenon already.
Mainly, nothing to worry about. If the pressure in the thermosifon is above a certain value, the expansion valve drips some droplets of water back into the water reservoir which you can observe through the little transparent water hose.
Above a lower value, the control board states "check exp.valve" -- it does seem to instruct you to do something but it's just a text people thought would be helpful at the time when the option was built in.
If cold water is added to the thermisofon to keep the set pressure, that little bit of cold water immediately heats up and expands. This creates a great increase of pressure if there is no expansion valve. The valve opens somewhere between 10-15bar.
Futhermore I have found out that when I set the preinfusion to 2.0 bar or under the pump does not get activated.
Setting a certain pre-infusion does not itself activate the pump.
The pump is activated when the pressure in the thermosifon falls below the set pressure. Thank you so much. You and Reiss have been such a great help! I really appreciate it! Fantastic support!
So put in other words; I do not have anything to be worried about?
Emil Rønnow post=17111 wrote: So put in other words; I do not have anything to be worried about?
I found what Reiss wrote about this a month ago:
the pressure reading is the pressure reading at the transducer, net of the offset value
this value fluctuates for two reasons
(1) when cold water is driven into the manifold, past the non return valve in the bottom of the manifold, it is then heated by the system and this causes thermal expansion of the relatively cold water by a tiny amount, yet because liquids are non compressible it causes the pressure in that section of the system to keep increasing until the expansion valve opens at 12-13 bar, which is what you will observe
(2) once the expansion valve has opened on the first heating cycle of the newly introduced cold water the pressure in that part of the system will cycle in response to the cycle of the heating element in the boiler
the system has been designed so you dont have to worry about the measured pressure at the transducer, but rather just set the pressure you want and the system gives you a repeatable result in the cup
where the measured pressure at the transducer is extremely useful is for fault diagnosis, so for this reason we have chosen to keep it visible to the operator
when we added the digital pre-infusion module to the LR we kept using the same manifold with the expansion valve in the top that has been used for years in many thousands of Fracino machines without issue
however with the addition of the digital module it brings the ability to display an over pressure message, and so it was felt we should add one
unfortunately this was programmed to display at 12.7 bar, which i think is too low, my preference is for it to show at 12 bar plus 10%, which would be 13.2 bar
so your choices are to ignore it, or if you prefer you can adjust the expansion valve fractionally so it opens at closer to 12 bar, but you are likely to need less than an eighth of a turn counter-clockwise to achieve this
Thank you very much for your help! I really appreciate it, Frans!
Btw If anyone has some good advice on extracting very light (nordic) roast on the LR, please dont hold back :-) Is the go-to recipe 6 bar preinfusion? For how long? And a longer brewratio, ex 1:2,5-3?
Emil Rønnow post=17120 wrote: Thank you very much for your help! I really appreciate it, Frans!
Btw If anyone has some good advice on extracting very light (nordic) roast on the LR, please dont hold back :-) Is the go-to recipe 6 bar preinfusion? For how long? And a longer brewratio, ex 1:2,5-3?
Wihout knowing the roaster and what they did, and what green beans were used, it's not easy to assess what extraction would best bring out the bean's pleasant characteristics.
Terms like 'light' / 'medium' / 'nordic' can mean anything. Roast color can be measured but usually roasters merely say "light" etc
It's possible to stop a roast curve 30s after "First Crack" starts which yields a very light bean, or lower heat and increase airflow before FC allowing the roast to continue for 2 minutes while still "keeping the pressure on" with enough increase in temperature to actively push all the chemical reactions inside the cellulose cells of the bean (tiny little pressure cookers). The same color bean may come out but the latter has much more taste.
I mostly use the 18g VST basket or the 18g IMS/Londinium basket. With roasts that I call light (Tonino #105 or above) I dose 19g, grind fine enough that the first droplets fall from the basket at 5-7s after pulling the lever at 6bar and getting 30g of espresso in 25-30s.
Frans Goddijn post=17122 wrote: [quote=Emil Rønnow post=17120]Thank you very much for your help! I really appreciate it, Frans!
Btw If anyone has some good advice on extracting very light (nordic) roast on the LR, please dont hold back :-) Is the go-to recipe 6 bar preinfusion? For how long? And a longer brewratio, ex 1:2,5-3?
Wihout knowing the roaster and what they did, and what green beans were used, it's not easy to assess what extraction would best bring out the bean's pleasant characteristics.
Terms like 'light' / 'medium' / 'nordic' can mean anything. Roast color can be measured but usually roasters merely say "light" etc
It's possible to stop a roast curve 30s after "First Crack" starts which yields a very light bean, or lower heat and increase airflow before FC allowing the roast to continue for 2 minutes while still "keeping the pressure on" with enough increase in temperature to actively push all the chemical reactions inside the cellulose cells of the bean (tiny little pressure cookers). The same color bean may come out but the latter has much more taste.
I mostly use the 18g VST basket or the 18g IMS/Londinium basket. With roasts that I call light (Tonino #105 or above) I dose 19g, grind fine enough that the first droplets fall from the basket at 5-7s after pulling the lever at 6bar and getting 30g of espresso in 25-30s.
One example of a roast and colour measurement is shown here: https://kostverlorenvaart.blogspot.com/2020/08/french-roast.html Thanks for your answer. I will try to mimic it. Regarding the coffee it is a Kenya from a danish roaster called CleverCoffee. A bit like La Cabra, The Coffee Collective, TW, Stillers coffee and so on. I know that roast colors and categorization is very subjective - but this one is best characterized as a light filter roast stopped very early in first crack. Very light and dense.
A little update - hope you can help me. My problem is that the pump is sometimes not turning on when pulling down the lever (both when flushing and brewing). If I keep the lever down the hx is going empty and only steam is coming out. What can be wrong? Is it the pump? Can a loose wire or something simple explain it?
if the machine is on and the boiler is pressurised, open the hot water tap and let hot water come out until the blue light illuminates; the pump should turn on with the blue light. does it? if it does the pump is fine.
It does come on. But is it really normal that the pump does not always engage when brewing? And letting the brewing path run dry? I am afraid to damage anything
no its not normal; you have high/rough spots on the pump lining as a result of the pump running dry at some point in the past. when the pump vanes come to rest on these high/rough spots in the pump liner the resistance is too great for the motor to be able to turn the pump
when the pump vanes come to rest in another position where the pump lining is not damaged the motor is able to get the pump turn and build torque, such that it has sufficient power to turn the vanes through the rough spots on the pump liner once it is turning
you either live with it or replace the pump unfortunately
Thanks for answering. Just to clarify, so when the pump is not engaged when pulling the lever (to create pre infusion pressure to fill the brew path), the water in the boiler will not be pushed out of the boiler (via a valve) exposing the heat element?
I do not fully understand how the LR is built. I know it is a hx, but must be somehow connected to the boiler since you recommend to set the pre infusion pressure to minimum 1.0 bar as the boiler. Can I find a diagram over how it works?
your machine, the LR, has a manifold in it the splits the water supply delivered from the pump into two streams with the addition of a manifold
(1) off one branch of the manifold comes a copper pipe that has an inlet solenoid on it. when the level probe in the boiler detects the boiler is low on water (water level drops below the bottom of the probe breaking the low voltage electric circuit) it signals to the Gicar control unit to open the inlet solenoid and turn on the pump and the blue LED on the front of the machine, and the boiler is refilled
(2) off another branch of the manifold is a copper pipe that connects directly to the end of the heat exchanger T fitting on the end of the boiler, with no regulation in the line
there is no pathway between the heat exchanger-thermosiphon circuit (what i call the preinfusion circuit) and the boiler; the regulation of the water level in the boiler is completely independent of the maintenance of the set pressure in the preinfusion circuit
the lower most branch of the manifold has the digital pressure transducer on it, which easily detects tiny changes in pressure in the system at that point and turns on the pump when the measured pressure is less than the target pressure you have set
if the boiler needs to be refilled and the pump binds then the low water alarm will activate and turn off the heating element if the boiler is not refilled within i think 25 seconds of the pump being actuated by the Gicar control unit
I have been in contact with the guy from who I bought the machine. He insured me that the pump has never run dry - I am certain that he takes care of his machines: He has just bought a new R24. If it is not because the pump has socked air what else could be the reason? Could it help to somehow adjust the pump?
Emil Rønnow post=17199 wrote: Thank you, Reiss! Now I understand.
I have been in contact with the guy from who I bought the machine. He insured me that the pump has never run dry - I am certain that he takes care of his machines: He has just bought a new R24. If it is not because the pump has socked air what else could be the reason? Could it help to somehow adjust the pump?
After writing the post above I pulled a nice kenyan espresso. Afterwards the pump was totally dead. Is it possible to manipulate it to force it to spin somehow with a screwdriver? (Saw it on a YT video with an Expobar rotaty pump) Is it possible to inspect the pump to try to find the reason? The pump in the store for the R is that the same pump in the R24? If not is it possible to fit the R24 pump in the R? Heard this should be quieter.
Emil Rønnow post=17201 wrote: The pump in the store for the R is that the same pump in the R24? If not is it possible to fit the R24 pump in the R? Heard this should be quieter.
They are different. The "24" indicates it runs on 24V whereas your current pump, while alive, ran on the same power that's in the wall socket, like 120V in the US / 230V in Europe.
with the machine unplugged from the wall you can try pulling the lever down and then holding the garden hose hard against the exit valve in the bottom of the plastic water tank (with the BWT water softening filter removed and the snap fittings removed from the end of the garden hose if there are any)
turn the garden hose on and the hydraulic pressure from the garden hose will most likely turn the stainless steel 8 vane pump, freeing it
you will know when you have freed the pump as water will run out of the group when you have the lever in the down position
as always please take extreme care when the lever is in the locked down position with no loaded portafilter on the group as the lever arm will fly up with speed and force if you bump it out of the locked down position
if you get water coming out of the bottom of the group with the lever down the pump is free; turn off the hose, return the lever to the resting position. try connecting the machine to the electrical supply and making a coffee
with the machine unplugged from the wall you can try pulling the lever down and then holding the garden hose hard against the exit valve in the bottom of the plastic water tank (with the BWT water softening filter removed and the snap fittings removed from the end of the garden hose if there are any)
turn the garden hose on and the hydraulic pressure from the garden hose will most likely turn the stainless steel 8 vane pump, freeing it
you will know when you have freed the pump as water will run out of the group when you have the lever in the down position
as always please take extreme care when the lever is in the locked down position with no loaded portafilter on the group as the lever arm will fly up with speed and force if you bump it out of the locked down position
if you get water coming out of the bottom of the group with the lever down the pump is free; turn off the hose, return the lever to the resting position. try connecting the machine to the electrical supply and making a coffee
kind regards
reiss.
Tried startet the machine again this evening and the pump turned on and ran about 15 sek. I pulled down the lever and the pump was turned on. Tried again and the pump did not engage.
What do you mean by “garden hose”? Just to clarify so I dont do something stupid.
um. by garden hose i mean the plastic thing perhaps 10 metres long and about 12mm internal diameter that you connect to an outside tap and water the garden with. you will need to remove any snap fittings from off the end of the hose so you have just the bare hose
happily the diameter of a standard garden hose is the same size as the exit hole in the bottom of the water tank, so the fit is good
the hydraulic pressure from the garden hose, liquids being non-compressible, provides a good way to free the pump if it binds in the liner
Thanks. That was how I understod it first, but thought I had mistranslated something. Do you think it can help with something? Because I am not totally comfortable with doing it - a dirty harden hose and bad water quality does not seems like the best combo with a nice LR.
Is there someway to qualify for free shipping in the shop if I buy for xxx£?
Just a hypothetical question: Is it possible that the pump is actually working but something is wrong with the preinfusion system so that the pump is not engaged when activating the preinfusion pressure via the pump?
If the pump does fill up the boiler when taking out water can I presume that the pump is working 100%? Last time I checked the pump did fill up the boiler. Can I check again? What if the pump does not work? Do I risk to burn out the heater element or the boiler?
[quote=Emil Rønnow post=17214] And the clicking sound is also very salient.
I don't hear any clicking in the video... If you focus on the first 5-10 sec of the video the sound is like “do... do.... do....”. I think the word “clicking sound” I have been using is a wrong term. It is more like a banging sound
you have high/rough spots on the pump lining as a result of the pump running dry at some point in the past. when the pump vanes come to rest on these high/rough spots in the pump liner the resistance is too great for the motor to be able to turn the pump
when the pump vanes come to rest in another position where the pump lining is not damaged the motor is able to get the pump turn and build torque, such that it has sufficient power to turn the vanes through the rough spots on the pump liner once it is turning
the fact that it has worked on this and other occasions to fill the boiler, but at other times pulling the lever has resulted in the pump binding is nothing other than a game of chance; the pump does not know whether it is raising the pressure in the pre-infusion circuit or refilling the boiler
if you try refilling the boiler ten times in a row i expect you will also get the pump to stop at a location where the pump motor is not able to turn the pump the next time the pump motor is turned on
Comments
I believe Reiss explained this in one of the messages about this phenomenon already.
Mainly, nothing to worry about. If the pressure in the thermosifon is above a certain value, the expansion valve drips some droplets of water back into the water reservoir which you can observe through the little transparent water hose.
Above a lower value, the control board states "check exp.valve" -- it does seem to instruct you to do something but it's just a text people thought would be helpful at the time when the option was built in.
If cold water is added to the thermisofon to keep the set pressure, that little bit of cold water immediately heats up and expands. This creates a great increase of pressure if there is no expansion valve. The valve opens somewhere between 10-15bar.
Setting a certain pre-infusion does not itself activate the pump.
The pump is activated when the pressure in the thermosifon falls below the set pressure.
Thank you so much. You and Reiss have been such a great help! I really appreciate it! Fantastic support!
So put in other words; I do not have anything to be worried about?
I found what Reiss wrote about this a month ago:
Btw If anyone has some good advice on extracting very light (nordic) roast on the LR, please dont hold back :-)
Is the go-to recipe 6 bar preinfusion? For how long? And a longer brewratio, ex 1:2,5-3?
Wihout knowing the roaster and what they did, and what green beans were used, it's not easy to assess what extraction would best bring out the bean's pleasant characteristics.
Terms like 'light' / 'medium' / 'nordic' can mean anything. Roast color can be measured but usually roasters merely say "light" etc
It's possible to stop a roast curve 30s after "First Crack" starts which yields a very light bean, or lower heat and increase airflow before FC allowing the roast to continue for 2 minutes while still "keeping the pressure on" with enough increase in temperature to actively push all the chemical reactions inside the cellulose cells of the bean (tiny little pressure cookers). The same color bean may come out but the latter has much more taste.
I mostly use the 18g VST basket or the 18g IMS/Londinium basket. With roasts that I call light (Tonino #105 or above) I dose 19g, grind fine enough that the first droplets fall from the basket at 5-7s after pulling the lever at 6bar and getting 30g of espresso in 25-30s.
One example of a roast and colour measurement is shown here:
https://kostverlorenvaart.blogspot.com/2020/08/french-roast.html
Wihout knowing the roaster and what they did, and what green beans were used, it's not easy to assess what extraction would best bring out the bean's pleasant characteristics.
Terms like 'light' / 'medium' / 'nordic' can mean anything. Roast color can be measured but usually roasters merely say "light" etc
It's possible to stop a roast curve 30s after "First Crack" starts which yields a very light bean, or lower heat and increase airflow before FC allowing the roast to continue for 2 minutes while still "keeping the pressure on" with enough increase in temperature to actively push all the chemical reactions inside the cellulose cells of the bean (tiny little pressure cookers). The same color bean may come out but the latter has much more taste.
I mostly use the 18g VST basket or the 18g IMS/Londinium basket. With roasts that I call light (Tonino #105 or above) I dose 19g, grind fine enough that the first droplets fall from the basket at 5-7s after pulling the lever at 6bar and getting 30g of espresso in 25-30s.
One example of a roast and colour measurement is shown here:
https://kostverlorenvaart.blogspot.com/2020/08/french-roast.html
Thanks for your answer. I will try to mimic it.
Regarding the coffee it is a Kenya from a danish roaster called CleverCoffee. A bit like La Cabra, The Coffee Collective, TW, Stillers coffee and so on.
I know that roast colors and categorization is very subjective - but this one is best characterized as a light filter roast stopped very early in first crack. Very light and dense.
My problem is that the pump is sometimes not turning on when pulling down the lever (both when flushing and brewing). If I keep the lever down the hx is going empty and only steam is coming out.
What can be wrong? Is it the pump? Can a loose wire or something simple explain it?
if the machine is on and the boiler is pressurised, open the hot water tap and let hot water come out until the blue light illuminates; the pump should turn on with the blue light. does it? if it does the pump is fine.
kind regards
reiss.
But is it really normal that the pump does not always engage when brewing? And letting the brewing path run dry?
I am afraid to damage anything
what do you currently have the preinfusion set to?
kind regards
reiss,
It just happened - but I kept the lever down, and when the brewpath was empty the pump turned on.
when the pump vanes come to rest in another position where the pump lining is not damaged the motor is able to get the pump turn and build torque, such that it has sufficient power to turn the vanes through the rough spots on the pump liner once it is turning
you either live with it or replace the pump unfortunately
kind regards
reiss.
Just to clarify, so when the pump is not engaged when pulling the lever (to create pre infusion pressure to fill the brew path), the water in the boiler will not be pushed out of the boiler (via a valve) exposing the heat element?
I do not fully understand how the LR is built. I know it is a hx, but must be somehow connected to the boiler since you recommend to set the pre infusion pressure to minimum 1.0 bar as the boiler. Can I find a diagram over how it works?
your machine, the LR, has a manifold in it the splits the water supply delivered from the pump into two streams with the addition of a manifold
(1) off one branch of the manifold comes a copper pipe that has an inlet solenoid on it. when the level probe in the boiler detects the boiler is low on water (water level drops below the bottom of the probe breaking the low voltage electric circuit) it signals to the Gicar control unit to open the inlet solenoid and turn on the pump and the blue LED on the front of the machine, and the boiler is refilled
(2) off another branch of the manifold is a copper pipe that connects directly to the end of the heat exchanger T fitting on the end of the boiler, with no regulation in the line
there is no pathway between the heat exchanger-thermosiphon circuit (what i call the preinfusion circuit) and the boiler; the regulation of the water level in the boiler is completely independent of the maintenance of the set pressure in the preinfusion circuit
the lower most branch of the manifold has the digital pressure transducer on it, which easily detects tiny changes in pressure in the system at that point and turns on the pump when the measured pressure is less than the target pressure you have set
if the boiler needs to be refilled and the pump binds then the low water alarm will activate and turn off the heating element if the boiler is not refilled within i think 25 seconds of the pump being actuated by the Gicar control unit
kind regards
reiss.
I have been in contact with the guy from who I bought the machine. He insured me that the pump has never run dry - I am certain that he takes care of his machines: He has just bought a new R24.
If it is not because the pump has socked air what else could be the reason?
Could it help to somehow adjust the pump?
Is it possible to manipulate it to force it to spin somehow with a screwdriver? (Saw it on a YT video with an Expobar rotaty pump)
Is it possible to inspect the pump to try to find the reason?
The pump in the store for the R is that the same pump in the R24? If not is it possible to fit the R24 pump in the R? Heard this should be quieter.
They are different. The "24" indicates it runs on 24V whereas your current pump, while alive, ran on the same power that's in the wall socket, like 120V in the US / 230V in Europe.
with the machine unplugged from the wall you can try pulling the lever down and then holding the garden hose hard against the exit valve in the bottom of the plastic water tank (with the BWT water softening filter removed and the snap fittings removed from the end of the garden hose if there are any)
turn the garden hose on and the hydraulic pressure from the garden hose will most likely turn the stainless steel 8 vane pump, freeing it
you will know when you have freed the pump as water will run out of the group when you have the lever in the down position
as always please take extreme care when the lever is in the locked down position with no loaded portafilter on the group as the lever arm will fly up with speed and force if you bump it out of the locked down position
if you get water coming out of the bottom of the group with the lever down the pump is free; turn off the hose, return the lever to the resting position. try connecting the machine to the electrical supply and making a coffee
kind regards
reiss.
What do you mean by “garden hose”? Just to clarify so I dont do something stupid.
happily the diameter of a standard garden hose is the same size as the exit hole in the bottom of the water tank, so the fit is good
the hydraulic pressure from the garden hose, liquids being non-compressible, provides a good way to free the pump if it binds in the liner
kind regards
reiss.
Is there someway to qualify for free shipping in the shop if I buy for xxx£?
Is it possible that the pump is actually working but something is wrong with the preinfusion system so that the pump is not engaged when activating the preinfusion pressure via the pump?
If the pump does fill up the boiler when taking out water can I presume that the pump is working 100%?
Last time I checked the pump did fill up the boiler. Can I check again? What if the pump does not work? Do I risk to burn out the heater element or the boiler?
I made a video of it:
And the clicking sound is also very salient.
What could be wrong?
I don't hear any clicking in the video...
I don't hear any clicking in the video...
If you focus on the first 5-10 sec of the video the sound is like “do... do.... do....”. I think the word “clicking sound” I have been using is a wrong term. It is more like a banging sound
you have high/rough spots on the pump lining as a result of the pump running dry at some point in the past. when the pump vanes come to rest on these high/rough spots in the pump liner the resistance is too great for the motor to be able to turn the pump
when the pump vanes come to rest in another position where the pump lining is not damaged the motor is able to get the pump turn and build torque, such that it has sufficient power to turn the vanes through the rough spots on the pump liner once it is turning
the fact that it has worked on this and other occasions to fill the boiler, but at other times pulling the lever has resulted in the pump binding is nothing other than a game of chance; the pump does not know whether it is raising the pressure in the pre-infusion circuit or refilling the boiler
if you try refilling the boiler ten times in a row i expect you will also get the pump to stop at a location where the pump motor is not able to turn the pump the next time the pump motor is turned on
kind regards
reiss.