Post By flynnaus
Post By Barry O'Speedwagon
Post By Andy
Post By Barry O'Speedwagon
Behmor 1600 not keeping temperature
Andy - HELP!
My Behmor for the last couple of months has been struggling to keep temperature and is under-roasting.
I'm using the temperature probe and 'Roasting Datalogger' to keep track of my roasts.
I pre-heat the oven to 110°C with 450g of beans in the drum (to try to get consistency) set to P2C++++, , after the initial full power it gets to around 250 - 260°C then struggles to hold 200°C for the rest of the roast.
I used to stop the roaster at around minus 1min to attain 50sec of rolling 2nd crack - around CS9 (my preference)
At best now it gets to about CS7 - just gets to 2nd crack. I've even tried shutting it down instead of letting it go through cool down to get some 2nd crack happening, intermittently starting cool down and stopping to turn the drum - I get an inconsistent (mottled) CS9.
I've noted that ambient temperature has an effect, the cooler the day, the more it struggles.
Last few roasts were done at about 14°C ambient. - It's getting cool now in the Adelaide Hills!
All regular cleaning with Simple Green spray and dry burns have been done. I've even taken the covers off to see if it was badly dirty inside - seems pretty clean.
Has anyone else had this issue?
What's the fix?
Thanks in advance,
I would say ambient temp is what's causing your roasting problems now. Also, 450g is a very large batch size for the Behmor even in warm temps.
I would definitely go for a smaller batch size. On a chilly winter morning in Sydney, I went from a usual 360g batch down to 340 while trying the P2C profile and finding even then I have to add time.
50 seconds of rolling second crack? In my roasting experience, that's more likely to result in CS11 (ie quite a dark roast) rather than CS9. I rarely venture into RSC, usually stopping before.
Pre-heat the Behmor to 110 degrees Celsius? I didn't it was possible to pre-heat that high and be able to start it.
My Behmor is behaving similarly, and has been for months now.
I've been doing 420g (P2C) consistently for the past couple of years, and this has consistently got me to second crack just as it hit the cooling cycle.
Now, however, I've had to reduce it significantly to even get it to rolling first - I'm down to 350G, and max additional time. Ambient temp isn't too much of an issue (or at least, wasn't until last night!) -- Brisbane has been pretty consistently warm all year.
I found if it went past 130°C it wouldn't start... just had to find the max!
Originally Posted by JojoS
Have a another look at Update 3 for the Behmor manual that outlines Important Maintenance Procedures.
Originally Posted by sysiphus
"Failure to perform this cleaning will lead to longer roast times and possible equipment failure"
Good to know! Thanks!
Originally Posted by Mickster
Huh?! What's the number reported from the wall chamber temp? How long do usually pre-heat? I'd be very happy if I can pre-heat to 100º, from my logs it'll be 5-6 mins :S
Originally Posted by Mickster
Sorry, can't help with your original problem. I've been roasting 200g batches. But, I'll try, since the problem is "keeping more heat" after the drop from the P2 profile setting, I doubt it's the batch size issue.
Is the 250-260º max is your usual max? If so, I'm betting on ambient temp. Try roasting indoor, or if you're already indoor, go to a smaller room?
If the 250-260º is lower that your usual max, it might be your electricity...
Or, upgrade to 1600+, technically you can roast even longer...
I am guessing that the temperature measurements are not taken from the side wall sensor.
Originally Posted by kutis
Not sure what happened with my original post???
I'm using Andy's USB temperature datalogger with the thermocouple sitting in a hole drilled in the side of the roaster.
The initial heat up is fairly normal but when the P2 profile sits on 75%, it used to maintain between 209 - 214°C but now barely keeps 200°C.
This does not roast the beans enough to get to 2nd crack in the allowable time.
Power is good - I do roast in the shed and teh ambient temps are dropping - I think this is looking more like the problem than anything else.
I only just read about the upgrade - looks good if able to extend the roast time just a little.
Roasting 1lb (454g) should be doable - seems like many are using less to get teh results they want.
My next step is to bypass the inbuilt controller and rig up an external one that will roast on temperature - not time like this one!
Last edited by Mickster; 18th June 2014 at 05:09 PM.
Originally Posted by Mickster
So, how many minutes did you normally pre-heat so it reaches 100º? I've read somewhere it's 2:30 secs before it can stop without the cooling cycle kicks in...
I believe that there was a suggestion to get it to 60 degrees Celsius on the the side wall sensor if pre-heating is desired for consistency other than the 2 minute time suggested for US 120V versions. I have yet to try it since it is summertime now in HK have done away with pre-heating. I did 90 second pre-heat last winter when ambient temperature in my kitchen was in the 15 to 18 degree Celsius range.
Hmm, I've been logging starting from minute 3, wall sensor usually reports 69-75º. 60º would be within 2:30 sec ballpark, seems about right. Though pre heat to a certain temp makes more sense for consistencies than time.
I was experiencing the same issue. I have roasted two 350g batches, one on P1 and the other on P2. For both these settings, they both failed to reach 2nd crack. I feel the beans are just baking in there. Was wondering if anyone had an update on what has/hasnt been working. Thank you in advance!
A bit more info may help:
P1 / P2 what? i.e. A/B/C? Presumably you've set the weight to 400?
Are you roasting outside or inside? What beans?
Have you tried adding a little bit of time to the roast?
Have you cleaned the fan and exhaust channels?
I put the beans in and preheat so in reality I am getting a little more time in my roasting.
I had to roast inside due to the cold and in Bendigo I was having to roast less and less because of the ambient temperature. I recently moved to Maddingley in an new house and I am now finishing my roasts with plenty of time where in Bendigo I was going to the very last second and still sometimes ruining out of time. Only 130kms difference but huge difference in roasting. Also huge difference in the grind settings. Who would have thought??
Thanks guys for the replies!
So I've normally used P3,C,1 with these particular beans (Brazil Yellow Bourbon) and have had decent results with this setting but recently it's been taking too long so I tried using P2 and P1 which didn't seem to make much of a difference. I roast outside but it's been pretty cold here in Sydney when I've roasted, approx 10-12 deg I think with a little wind. I've cleaned out the exhaust and the sensor area with no change.
So reading Dan's reply, I'm guessing the ambient temperature is maybe what's affecting my roast times... But it's weird that regardless of whether I change from P2 to P1, there is not much difference in my roasts i.e. I run out of time before the roast reaches 2nd crack.
Just try reducing the weight of beans by another 20g and see how you go.
The ambient temp. certainly makes a difference (though I tend to get away with 380g doses on 400 P2 B outdoors in Canberra.....P3 does take extra time in the cold weather...had to extend it by 2 mins and haven't tasted the result yet).
EDIT: The other thing I do using P2 is switch the power to 75% when the automatically profile is about to switch power down to 65% (after about 12 minutes on the 400 P2 B cycle).
1: Preset profile + LOWER air temperature = Lighter Roast.
2: Preset profile + HIGHER air temperature = Darker Roast.
It's really not an accident that this thread gets action in June and July.
Roasters draw in air and that air needs to be heated. If you are using the same weight of beans and applying the same amount of heat it has to result in a lighter roasted coffee this is even more noticeable on a commercial sized roaster as it draws more far more air into the drum that needs heating before it has an effect on the beans.
Also keep in mind that the temperature of your green beans is also likely to be far lower at this time of year, worse if you keep them in the shed.
Options in no particular order are:
a: roast longer
b: roast hotter
c: use less beans
e: a mixture of all the above
As in the above replies, the easiest fix is to reduce the weight of beans and apply the same heat profile to get the result you want and I agree that's the best option.
I'm not a fan of pre-heat as it can add a variable that's hard to replicate each time and I would much rather reduce the weight which will keep the profile similar to the warmer months. As we move into spring you will add some beans and summer add some more.
Hi Andy I have just Joined and i am unsure how to post can only see the privet message button?
Seem like you've worked out how to post
Originally Posted by paulcassidy
Hi Andy, thanks for the reply. The thing is, I have tried all that you've listed. I pre-heat. I have reduced the size of the beans to 350 from 400. I've tried going hotter to P2, C, 1 as well as P1,C, 1 but beans didnt reach 2nd crack even with added time for both profiles. Do you think there may be an internal problem going on?
Thanks for that Barry,
I'll try change roasting places and see if it makes a difference!
Unfortunately, I am unable to switch the power as I havent upgraded to the Plus yet.
I was having a similar problem.
I have done 330 roasts in my Behmor. I was finding that it was getting to around 40°C less than it did when it was new - for no reason. Same weight (312g) same Profile (1lb P2 C). Yes the ambient is different but it's been doing this for a year. Behmor were very helpful and said perhaps the sensors were kaput and Andy sent me new ones to try (even though machine out of warranty) but it made no difference.
When you are used to pulling the roast with 7 minutes to go and are now having to let it run until the end and still ending up with CS9 and that 'baked' not 'roasted' feeling and you have people telling you that your roast plot from RoastMonitor is within spec and looks normal - you just give up - I did anyway. It's not like the thing was that expensive.
Anyway I've moved on as that seemed like the only viable option.
Another factor to consider is whether you are sharing your behmor electrical circuit with other power intensive devices such as electric oven, iron, heater, i hope this helps