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Topic: I Roast 2 always exceeding temperature (22 msgs / 752 lines)
1) From: J.B.
Hi,
the IRoastV2 i bought some days ago (european version) is always 
exceeding the temperature set in the custom settings / or even preset  - 
no matter what. It's not like just a few degrees - i chose 160 C = 320 
F which is the minimum temperature as setting for stage 1 for 7 
minutes, and it went on to 200C = 392 F within a few minutes and 
reached 213C = 412F within these 7 minutes. The second crack was 
reached at the end of those 7 minutes.
Beans: Brasil Santos, Kenia AB [for each kind some roast were with less 
some with more beans - nearly no difference]
Is there no way to get a roast longer than 7 minutes ? 
Or is my IRoastV2 not working properly at all ?
Jan

2) From: Aaron Peterson
On 3/28/06, J.B.  wrote:
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I have the same issues.  I have experimented with some modifications
on the chaff collector to allow greater air flow, making it harder for
the iRoast to heat the chamber as quickly.  I've had mixed results
though.  My iRoast2 programmed temperatures are much lower than what I
actually get too.  I program 355 and get 420 F, etc
and when I look at the temperatures during the roast on the iRoast
display it shows 383 when the beans are at 425.  then when the beans
are hotter, around 455-460 it shows...  383F.  I don't pay any
attention to onboard temps any more.
With the iRoast2 assembled per hearthware instructions my longest
roasts have been around 9 minutes and those were burnt.
Aaron Peterson
Versailles, KY

3) From: Woody DeCasere
WOW that seems strange my reading are generally always lower than the
programmed temperatures
On 3/28/06, Aaron Peterson  wrote:
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d
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s
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--
"Good night, and Good Coffee"

4) From: Sandy Andina
--Apple-Mail-188--88735125
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i-Roasts vary wildly--some (like my original) run hot and others  
(like my i-2) run cool, and others have reported the opposite  
results.  You can get a hot-running machine to run slightly cooler by  =
using an extension cord (the longer and heavier the better), and you  
can even out the voltage by plugging into a variac.
On Mar 28, 2006, at 11:47 AM, J.B. wrote:
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setting  
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within  
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The  
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Sandy
www.sandyandina.com
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i-Roasts vary wildly--some (like =
my original) run hot and others (like my i-2) run cool, and others have =
reported the opposite results. You can get a hot-running machine to =
run slightly cooler by using an extension cord (the longer and heavier =
the better), and you can even out the voltage by plugging into a =
variac.
On Mar 28, 2006, at 11:47 AM, J.B. wrote:
Hi, the IRoastV2 i bought some days = ago (european version) is always exceeding the temperature set in the = custom settings / or even preset = - no matter what. It's not like just a few degrees - i chose 160 = C = 320 F which is the minimum temperature as setting for stage = 1 for 7 minutes, and it went on to 200C = 392 F within a few = minutes and reached 213C = 412F within these 7 minutes. The = second crack was reached at the end of those 7 minutes. Beans: = Brasil Santos, Kenia AB [for each kind some roast were with less some = with more beans - nearly no difference] Is there no = way to get a roast longer than 7 minutes ?Or is my = IRoastV2 not working properly at all ? Janhomeroast mailing listhttp://li=sts.sweetmarias.com/mailman/listinfo/homeroastTo change your personal list settings (digest = options, vacations, unsvbscribes) go to http://=sweetmarias.com/maillistinfo.html#personalsettings = = --Apple-Mail-188--88735125--

5) From: J.B.
I would really love to change my fast-burning I-Roast into a cool 
running one because with my one it's simply nonsense to make any 
settings as every roast is the same.
At the moment I really don't want to spend more money on a variac or 
other mods for the IRoast, because I just bought the IRoast because it 
seemed easier and better than buying a variac for my CR 100.
can't describe how dissapointed I am about the IRoast :(
Anyone yet tried to contact Hearthware in order to change her/his hot 
running one for a new one ?  IMHO this is a major defect.
Sandy Andina wrote:
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6) From: Brent - SC/TO Roasting
My understanding is that Hearthware customer service is very good and
is aware of this type of fluctuation among the machines.
My experience with their customer service for a part replacement was OK.
--
Brent
Roasting in an SC/TO & i'Roast2
On 3/28/06, J.B.  wrote:
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7) From: Bob Adams
Want to make sure we are talking about the same thing
here. Jan says her
roaster is exceeding inputted temps, as reported on the readout of the
roaster, right? Aaron, are you talking TC readout or iR readout?
I think an iR that is exceeding inputted temps and reporting those excessive 
temps is
defective. Both my iR's would increase fan speed to cool back down to 
inputted temps.
Bean mass temps will be much higher but this is expected due to the location 
of the iR's temp probe.
I think that it is important to relate which temp reading we are using--TC 
or onboard.
Bob

8) From: David Echelbarger
J.B.  I'm assuming you experimented with different temps.  I thought I =
had a
hot I-Roast 1 but got it to work really very well using the following =
set
up.  I had nice separation between cracks.  Regular Hard Bean Profile:  =
2 at
320; 3 at 375; set to 10 at 415.  Peaberry and Soft Bean Profile: 2 at =
320;
3 at 360; set to 10 at 400  I usually ended dumping between 3 to 5 =
minutes
in the 3rd stage for City Plus or Full City Roasts -- a bit quicker for
peaberries.  Maybe up to 6 minutes into the 3rd for a Vienna.  I did 183
roasts in it, but also was running a stainless popper as well.  Then I =
went
to an RK Drum and haven't used the I-Roast since, although still use the
popper occasionally.

9) From: S. Kimmel
This is a multi-part message in MIME format.
I suspect my iRoast2 might also be running hot. My first roast (and =
only, so far) was a Guat. 1/3 cup of beans went to Vienna in 5 minutes =
on Preset 2. The result was bitter in a press - 3 minutes then press.
Any suggestions to improve this?
Sheila 

10) From: S. Kimmel
This is a multi-part message in MIME format.
When I mentioned in my last post that I believe mine exceeds temperature =
as well, I'm using a dryer vent up to the exhaust fan in the bathroom =
ceiling, so I don't trip the condo smoke alarm.
Would that make it hotter?
Sheila 

11) From: Aaron Peterson
On 3/28/06, Bob Adams  wrote:
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ive
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ion
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Yes, my onboard temp is always arbitrary and lower than my TC readout.
 However, temperatures input into a program are not usually exceeded
according to the onboard thermometer.  I can envision scenerios where
they would though, if kicking up the fan speed was unable to
successfully bring the temperature down (if there's lots of chaff in
the collector for instance).
I think it is a huge defect either way you cut it, but I'm happy to
have some reasonable method to roast beans.  After using mine for a
month or so now, I think the iRoast suffers from 2 major design flaws:
first, that the temperature of the beans isn't measured.  second, that
the temperature programs only seem to use variable fan speeds to
control the temperature and there is no way to also vary the power
going to the heating element.  A possible 3rd flaw is that there is no
way my on board temperature readout can be correct, even at measuring
the air stream temperature.  When my beans are at 450 F according to
my TC, the readout still says 383 F.  How do beans get to 450 if the
air stream never breaks 400?
I wish there was a temperature-freeze button on the iRoast, so that
any time during the roast I could push this mythical button and the
iRoast2 would do whatever it had to do to keep roasting at that
temperature until I hit the button again to unfreeze it and allow the
temperature to continue to rise.  This would only work if there was an
accurate thermometer in the beans mind you, but if all this came
together I would be in heaven with the iRoast2.  The only other reason
I would go to any other roasting method would be to roast larger
batches, and the iRoast2 wasn't meant for that market anyway.
Sorry for the rant,
Aaron Peterson
Versailles, KY

12) From: Bob Adams
Beans are not at 450--roasting chamber is at 450. Chamber is that much 
higher due to back pressure from chaff collector, chaff, and screen. Temp 
builds up in the chamber. We've seen that is necessary with our experiments 
to relieve this back pressure resulting in baked beans.
I'm sure the manufacturer ran many prototypes to get to this combination of 
collector, chaff and screen. It is a compromise, with the amount of chaff 
given off as the biggest variable.
Aaron I think you were right in thinking that a more free airflow with the 
ability to restrict it at will could result in a more controlled roast. When 
I removed half the screening the roast chamber would not heat up 
sufficiently =stalled roast. However I now can cover the lid with a large 
polypro scoop and create backpressure as needed to get the temps I want. The 
lower the scoop over the lid=higher backpressure=higher temps--conrtrollable 
temps.
A much more interactive roasting process-scoop has a handle which keeps my 
hand from burning. Give it a try-new lid from Hearthware is pretty cheap-
Bob

13) From: Bob Adams
This is a multi-part message in MIME format.
If the dryer vent is connected to the iR with chaff collector and lid =
still attached then I believe you are changing the dynamics of the =
backpressure resulting in serious overheating.

14) From: Michael Wade
FWIW, I placed a bead probe just below the inlet holes on my iR2 and found 
that the inlet air column temp runs about 70 degrees F above the indicated, 
give or take a half-dozen, and is fairly consistent.  I had to pull the 
probe before stage 3 as the teflon insulation on my thermocouple is only 
rated to 500 degrees F.
When I place the probe in the chaff collector the temperature lags 
considerably behind indicated, but eventually comes pretty close to 
indicated before the end of each stage as the bean mass and roaster mass 
come up to temp.
My assumption (with all the caveats that word implies) is that without 
provision for a probe in the roast chamber the designers introduced a 
correction factor in an attempt to derive roast chamber (bean mass?) temp 
from the only sensor they had.  Designing to a price point must be 
frustrating for an engineer!
I've tried recording both indicated and chaff collector temps but it serves 
no purpose and distracts me from paying attention to the roast.   I plan to 
purchase a rigid probe and drill the iR2 to place it in the bean mass out of 
curiosity and eventually consistency, but meantime I'm experimenting with 
programs and getting (finally) some pretty good coffee.
One odd thing has cropped up, there seems to be a 60 second or so lag when 
the machine hits stage 3. The temp starts rising but not to the program 
setting, then after a minute or so it takes off aggressively and levels out 
maybe 10 or more degrees above program.  Its almost as though a "soft start" 
is programmed in the machine.  Anyone else noticed this?
Michael Wade

15) From: Aaron Peterson
All of my temperature readings are via TC probe in the bean mass.  I
threaded it around the gasket in the bottom of the roast chamber.  If
you're interested in seeing what that looks like there are some
pictures here:http://alpete.com/picturesDidn't require any drilling or anything.
Aaron Peterson

16) From: Kit Anderson
I made a rigid probe with the TC from Tom. I had a probe from dead 
thermometer that I cut off both ends, pulled out the wires, and threaded 
the new probe into the tube. This goes into a hole drilled in the top 
through the chaff collector and the plate it rests on. Rigid probe. 
Works great.
I have found that the air temp at the top of the chamber is within a few 
degrees of the bean bed and that the bean bed temps corresponds with 
Tom's pictorial page... e.g. 1st crack at 410 and ends at 426.  So, I 
feel confident that this probe is system pretty accurate.
I program 350 for 4min and 400 for 6. When the beans get to 420, I turn 
down the voltage with a variac to slow the ramp to 430 until all the 1st 
crack has finished. Then I turn it back up.
Kit
Michael Wade wrote:
 >I plan to purchase a rigid probe and drill the iR2 to place it in the 
bean mass out of curiosity and eventually consistency, but meantime I'm 
experimenting with programs and getting (finally) some pretty good coffee.

17) From: Myron J
This thread ran a few months ago.
I have an IROAST1, european model..and it too, always runs about 4:30 to 
first crack...6 minutes end of roast..NO MATTER what temps i set it for.
I have gone down to the minimum of 160 degrees C and run it at preset 1..All 
variations seem to have to do with Chaff amounts and ambiet temp.
I have been corresponding with Ivo of Holland and some people at Iroast in 
the States. They all seem to think the machine is "normal"  and Ivo 
suggested drilling holes in the chaff collector to allow more air flow.
It is not only a matter of it running "hot" but the fact that changning the 
settings does not effect results worries me.
So...do I drill holes in the Chaff collector???
Myron Joshua
Kibbutz Kfar Etzion
90912
Israel
+972-(0)2-9935 178

18) From: Randy Rusch
I have the original version of the i-Roast but it sounds like the cup in the
chaff collector is not seated firmly. If you shake the chaff collector
assembly (removed from the chamber) does the cup rattle around? If so place
washers or a ball of foil between the top of the cup and the bottom of
the screen. This traps as much chaff as possible under the cup and reduces
fouling of the upper chaff screen.
With the above mod a 150 gram load and a program of
4min @163C
5min @ 176c
6min @ 190C / till the end of the roast
This should get you to the start of 2nd crack around 11 - 13 min. Use
temperatures that keep the fan running in high speed all the time.
Chaff plugging the top screen will cause the temperature to go vertical out
of control.
This process worked great on the original (US) version, I hope it applies to
the newer version.
Good Luck
Randy

19) From: Myron J
This is a multi-part message in MIME format.
Randy..
I alread "fixed" my chaff collector with a spring..(which did solve the initial whacky roasts i got)..so that is not the issue at present.
Myron Joshua
Kibbutz Kfar Etzion
90912 
Israel
+972-(0)2-9935 178

20) From: Myron J
Michael Thanks for the idea.about loosening the chaff collector.
Another list memeber sent me an off line report of similar problems by him 
and noted that his IRoast, european model, roasted hot at 160 degrees C..and 
(apparently) roasted less hot at 195!! (Maybe due to fan speed??)
About the Kona..i am chicken to Roast it while i experiment with the Iroast.
In general my 6 minute roasts can be very tasty..
Myron Joshua
Kibbutz Kfar Etzion
90912
Israel
+972-(0)2-9935 178

21) From: Michael Wade
Myron:
I would also be very concerned about the machine not responding to ANY 
change of setting.  Have you logged the indicated temperature, say every 30 
seconds, during a roast?  If you could post your programmed temps and the 
resulting indicated temperatures maybe we could make a better guess about 
what's happening.
Does the machine ever level off at a temperature and then cycle the fan 
speed to keep the temperature constant?
I wouldn't make an irreversable change like drilling more holes in the top 
without experimenting with a non-destructive equivalent first.  I know it 
will get chaff all over the place, but if you loosen the top and allow a 
larger amount of air to flow it should tell you something about whether 
that's the direction to go.
Maybe jam a small wad of folded aluminum foil under one side to control the 
size of the gap and keep it constant?
Oh, and how did your Kona turn out?
Michael Wade

22) From: Michael Wade
Myron:
I absolutely understand about holding off on the Kona.  I bought one of the 
Panama triple-packs and I'm not even going to open the bag until I'm much 
more comfortable that I can produce exactly the roast I want on demand.  I'm 
getting close, but not there yet.
Good luck cleaning up that chaff...
Michael


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