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10/19/2021 6:22 AM
Welcome tarunk!

10/17/2021 12:40 PM
Ploni and nader fouad, Welcome!

10/15/2021 2:19 AM
merlot85, maycondelpiero and hoeltz, Welcome !

10/14/2021 10:06 AM
Thanks for the addition to the group. Seriously considering building a drum roaster along the lines of oldgrumpus's. Love the design and craftsmanship.

10/14/2021 4:00 AM
Morning, ar3mia ! and... coffee drink

In Memory Of Ginny
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Burrr..too..cold!!!
oldgearhead
I was about to run out of coffee. Even though its been very cold in our unheated garage, I simply just had to roast coffee anyway. So I loaded up 5 quart jars with 14 oz of greens in each and headed for the garage. The temperature when I started was 17?F. I set the heater to 1150 watts and the ambient air baffle to 'Siberian'.

1) First load was some low test weight (8%M) Ethiopian Sidamo Decaf - I had to stop the roast at 9.5 minutes because it was going too fast and my blower intake air was 134?F, a bit hotter than I like. The resulting batch looks normal but I don't really like decaf anyway.

2) Dropped the wattage to 1065 and started the second batch of the same decaf. The results were much better with a 12 minute total roast time and a blower inlet air temperature of 112?F.

3) Next I roasted two quarts of Bob-O-Link. You know the high-grown Brazilian who's flats turns dark early and the bean puffs up to over twice its starting size. These turned out very nice with a wattage of 1100 and a time of 12 minutes.

4) Finally I roasted a quart of sun-dried Kenya AA. It seemed a little reluctant to get going so I upped the wattage slightly to 1175 at the 6 minute point in the roast. I got a 12 minute roast that smells great.

The garage temperature two hours later was 34?F. This heat gain can be traced to the sun warming up the garage door to 50?F, not the waste heat from my body. A new record (17?F)! My previous low starting temperature was 22?F.
oldgearhead attached the following image:
dsc_9507_2.jpg
turtle
I know what you mean.... I have been drinking Folgers and other grocery store coffee blended to get something drinkable.....

I am contemplating roasting inside which I have never done (too much chaff and mess)

Desperate times require desperate measures.

My last roast outside was at 38? which took a fair off set for the cold on the outside of the roasting chamber. I was very surprised at how nice it came out
Mick - "Drinking in life one cup at a time"
"I'd rather be roasting coffee"

Roaster 1: San Franciscan SF-1
Roaster 2: Hottop B-2K+
Roaster 3: 2 kilo Chinese drum
Grinders: Mazzer Major - Forte BG (x3)
Pour over: Hario - Bee House - Chemex - Kalita - Bodum
Drip: Bunn CWTF15-1 & CW15-TC (commercials)
Espresso: Pasquini Livia 90 auto
Vacuum: Cona - Bodum
Press: Frieling - Bodum Colombia
ciel-007

Quote

oldgearhead wrote:

... I was about to run out of coffee. Even though its been very cold in our unheated garage, I simply just had to roast coffee anyway...



Although outside temperatures here frequently plummet to -25F, I like to keep my workshop at about 40F. This is my first Winter roasting with gas, and it's wonderful.

The 200 lb BellaTaiwan (XJ-101) is now permanently installed in the workshop. It is sitting against the outside wall, through which the gas conduit and chimney are safely routed. A few months ago, when the workshop was much warmer, the gas valve provided far more power than was ever required to roast 1kg loads to near perfection in about 13 minutes. However, when the ambient temperature dips down to 40F, the valve may sometimes be turned all the way to maximum flow in order to repeat this profile. The most critical segment of the roast is ensuring that the greens spend 6.5 minutes in order to reach a BMT of 330F. As it turns out, that is relatively easy to accomplish with my newfound companion - ARTISAN. Having Artisan displaying BMT and ET curves on the Thinkpad allows me to enjoy every single moment I spend in command of the gas and air flow valves.

Last Winter, the electric Hottop (and I) did not cope as well as the gas powered BellaTaiwan on cold days. When temperatures plummeted to 40F, browning 345G of greens in the Hottop added 3 extra minutes to the overall roasting time. Last Winter, using the Hottop to roast 1 Kg of greens, back to back, gave me the shivers.

Ciel
Ciel... seeking Heaven in my cup with ................................................................................................................. EXPOBAR Brewtus II - MAZZER Mini E - MAHLK�NIG Vario - GeneCafe - RAF-1 Extreme (Modified B-2 HOTTOP) - BellaTaiwan XJ-101
oldgearhead

Quote

turtle wrote:

I know what you mean.... I have been drinking Folgers and other grocery store coffee blended to get something drinkable.....

I am contemplating roasting inside which I have never done (too much chaff and mess)

>snip<

.
Smoke was my problem yesterday. I had to open the garage door during cooling to let it out and the outside air was hovering around 10F. However, it wasn't altogether a bad thing because it only took 2-3 minutes to cool each batch. I'm still trapping the chaff in the RC with great results with all but a few dry processed beans...
We sampled the Kenya AA this morning: it was pretty good for only 19 hours rest...
JETROASTER
Upstate NY has been kicking around some really low temps for a couple weeks now. I roasted last night at -4dg. The only issue has been tank-freeze, but it is a problem.
2 or 3 loads in and fuel pressure starts dropping off. I'm so done with winter. Cheers, -Scott
dfluke
I spent most of last year in my "roll down plastic walled" roasting area but installed a garage heater this year. I need to add insulation to the garage, but hey, better than those puny ceramic heaters, although more expensive. I only roast one or two times per week so it's decently bearable. I feel your pain though. We've been lucky this year with a milder winter in NE Kansas.
ciel-007

Quote

freshbeans wrote:

Upstate NY has been kicking around some really low temps for a couple weeks now. I roasted last night at -4dg. The only issue has been tank-freeze, but it is a problem. 2 or 3 loads in and fuel pressure starts dropping off. I'm so done with winter. Cheers, -Scott


Scott, low gas pressure can be most troublesome when trying to roast with propane in cold weather.

In order to minimize that possibility, I installed two propane tanks, and connected them via a Rego two stage regulator. The first stage (Rego 7525B4) features an Automatic Changeover mechanism. In a nutshell, this first stage is designed to automatically switch the gas supply from the empty tank (low pressure) to the full tank as the propane pressure drops to an unusable level.

Here are photos showing the Rego 7525B4 Automatic Changeover valve, and the two propane tanks which are located outside my workshop.

Ciel
ciel-007 attached the following images:
hro_rego.jpg hro_gas_tanks.jpg

Ciel... seeking Heaven in my cup with ................................................................................................................. EXPOBAR Brewtus II - MAZZER Mini E - MAHLK�NIG Vario - GeneCafe - RAF-1 Extreme (Modified B-2 HOTTOP) - BellaTaiwan XJ-101
JETROASTER
I made that switch a number of years back, it certainly helps. More recently I changed the height of where the flame propagates....lost some combustion efficiency, and now have to throttle about 25% higher. That plus the temps are killing me.
Please send heat. Thanks, Scott
JETROASTER attached the following image:
tanks_1.jpg
turtle
I roast outside and usually winter is not that much of an obsticle as we don't hve very hard winters usually.

The past week has been a killer (record breaker) and there is too much snow to move to set up outside and who wants to stand around at sub zero temps trying to burn beans.

Pulled the last of my espresso roast today.

Not sure what I am going to do tomorrow..... Tea and scones maybe ?!?!?!?!
Mick - "Drinking in life one cup at a time"
"I'd rather be roasting coffee"

Roaster 1: San Franciscan SF-1
Roaster 2: Hottop B-2K+
Roaster 3: 2 kilo Chinese drum
Grinders: Mazzer Major - Forte BG (x3)
Pour over: Hario - Bee House - Chemex - Kalita - Bodum
Drip: Bunn CWTF15-1 & CW15-TC (commercials)
Espresso: Pasquini Livia 90 auto
Vacuum: Cona - Bodum
Press: Frieling - Bodum Colombia
ciel-007

Quote

freshbeans wrote:

I made that switch a number of years back, it certainly helps...



Scott, if I understand the hookup in the photo, the T connector places both tanks in parallel, thus allowing them to discharge as a pair.

Ciel
Ciel... seeking Heaven in my cup with ................................................................................................................. EXPOBAR Brewtus II - MAZZER Mini E - MAHLK�NIG Vario - GeneCafe - RAF-1 Extreme (Modified B-2 HOTTOP) - BellaTaiwan XJ-101
beanut
Scott,

I used to use a few propane tanks for my kiln. What i wound up doing in winter was putting each tank in a big blue rectangular bucket so the water came up 3/4 of the way to the top then string on old metal coat hanger across the lip with a big v so it was hanging just above the water. Then hang one of those single cup coffee warmers off of it the kind that looks like a spiral florescent bulb and plugs in.

This kept the water in the 80 or 90 degree range and allowed me to get the most propane out of the tanks.

You could probably just fill it with warm water since you wont be roasting for hours....or maybe you will?
Beanut
GrinExpobar brewtus IV, MK K30 vario, Gene Cafe
JETROASTER
Ciel, parallel is correct. Less flow from each tank= less freeze. ....which leads to Beanuts experience with the kiln.
When I first noticed this issue years ago, I stumbled upon a ceramics forum and found the kilns causing the same situation. That's where i picked up the idea of running multiple tanks in parallel.
Beanut, I like the water bucket idea, quite clever!! For the moment, I'm storing the tanks in my ambulance which is plugged into shore power. The old O2 closet provides a reasonably safe enviroment to keep them a bit warmer. I normally try to run for a few hours. I'll see how the 'pre-warmed' tanks work out, if that doesn't do the trick, I'll try the immersion. Nice idea.
Cheers, Scott
ciel-007

Quote

freshbeans wrote:

... I roasted last night at -4dg. The only issue has been tank-freeze, but it is a problem. 2 or 3 loads in and fuel pressure starts dropping off...


Scott, because your propane tanks are hooked up in parallel, and because the pressure is allowed to decline in both tanks at the same time, that may lead to potential flow/pressure problems on very cold days. My two propane tanks are not hooked up in parallel, and they are not allowed to discharge as a pair; that hook up has performed flawlessly throughout the Winter so far.

The Rego 7525B4 Automatic Changeover mechanism keeps both tanks isolated for one another. The Rego valve allows only the first tank to discharge, while keeping the second tank fully charged. It is not until the pressure in the first tank decreases to an inadequate level that the Rego automatically switches to the second tank, which has been kept fully charged until needed.

So far this Winter, the Rego 7525B4 Automatic Changeover valve has worked very well. Despite temperatures frequently plummeting to -25F, I have always had sufficient propane gas flow/pressure to push my 1Kg BellaTaiwan to full roasting power at will.

Ciel
ciel-007 attached the following image:
hro_rego_1.jpg

Ciel... seeking Heaven in my cup with ................................................................................................................. EXPOBAR Brewtus II - MAZZER Mini E - MAHLK�NIG Vario - GeneCafe - RAF-1 Extreme (Modified B-2 HOTTOP) - BellaTaiwan XJ-101
JETROASTER
Hi Ciel,
I will likely investigate the Rego style set-up soon. It will probably work nicely when I start mounting this madness into the truck. I'm sure it will also allow me to change tanks on the fly, plus the tank freeze benefits.
(this is why HRO is so awesome!)
I still have to solve my combustion efficiency issues, but this will be very useful all the same.
Cheers, -Scott
ciel-007

Quote

freshbeans wrote:

Hi Ciel, I will likely investigate the Rego style set-up soon... it will also allow me to change tanks on the fly, plus the tank freeze benefits... (this is why HRO is so awesome!)...


Scott, the Rego valve system in question has two stages. Above, I talked about the first stage (7525B4) which features an Automatic Changeover mechanism.

However, for use in cold weather, the second stage (LV3403B4) is perhaps even more important. This second stage features a regulator equipped with an oversized orifice. This large 1/4" orifice can easily handle propane flow requirements up to 450,000 BTU?s/hr; most importantly, it greatly reducing the probability of freezing in very cold weather.

Ciel
Ciel... seeking Heaven in my cup with ................................................................................................................. EXPOBAR Brewtus II - MAZZER Mini E - MAHLK�NIG Vario - GeneCafe - RAF-1 Extreme (Modified B-2 HOTTOP) - BellaTaiwan XJ-101
JETROASTER
Does this only serve to prevent freeze at the regulator, or does it somehow reduce freeze within the tank valve assembly?
Thanks, Scott
ciel-007

Quote

freshbeans wrote:

Does this only serve to prevent freeze at the regulator, or does it somehow reduce freeze within the tank valve assembly?


Scott, as you know, I am new to gas roasting. However, I have done some reading about the impact of cold weather on liquid propane installations - since that very much applies to my situation.

Liquid Propane has a boiling point of -44F. Since propane turns to vapor when the temperatures is above -44?F, it shouldn't freeze when the temperature drops to -25F, as it does where I live and roast. So why on earth do some propane fired roasters malfunction in cold weather?

I did quite a bit of searching for answers. What I discovered was that some (most?) batches of propane contain quite a bit of moisture (water contamination). When we get our tanks filled with propane, there is likely to be some amount of moisture contaminating in the fuel. Under the right set of conditions, when the temperatures plunges below freezing, that moisture will form ice crystals; those crystals are likely to plug up the orifice found inside the regulator assembly. The smaller the orifice, the greater the probability of clogging that valve with ice crystals, and therefore impeding/stopping the gas flow. That risk can be reduced significantly by I opting for multi stage regulation in which the second stage valve features the largest possible orifice - which is what I did with the Rego assembly described above.

This link explains how moisture impacts gas regulators in cold weather:

http://www.google...5890,d.aWw

Ciel
Ciel... seeking Heaven in my cup with ................................................................................................................. EXPOBAR Brewtus II - MAZZER Mini E - MAHLK�NIG Vario - GeneCafe - RAF-1 Extreme (Modified B-2 HOTTOP) - BellaTaiwan XJ-101
Omega
I roasted 3 batches today and fortunately, it was 50*F this afternoon. No gas fired issues at those temps. I've roasted in temps just above freezing without propane flow issues. But, if I ever encounter the problem, I'll just try some of the tips I read here.

BTW, I live in southern Washington state where it is very mild for this time of year.

Barry
turtle
38? but got in 2 half pound roasts today.

Shoveled away the ice and snow to make room for the roaster

i1066.photobucket.com/albums/u414/turtle-web/food/coffee/roasts/2-23-2015_cold_zpsvqgvlhna.jpg

i1066.photobucket.com/albums/u414/turtle-web/food/coffee/roasts/2-23-2015_cold_btch_roast_zps6egdkuky.jpg
Mick - "Drinking in life one cup at a time"
"I'd rather be roasting coffee"

Roaster 1: San Franciscan SF-1
Roaster 2: Hottop B-2K+
Roaster 3: 2 kilo Chinese drum
Grinders: Mazzer Major - Forte BG (x3)
Pour over: Hario - Bee House - Chemex - Kalita - Bodum
Drip: Bunn CWTF15-1 & CW15-TC (commercials)
Espresso: Pasquini Livia 90 auto
Vacuum: Cona - Bodum
Press: Frieling - Bodum Colombia
ciel-007

Quote

turtle wrote:

... Shoveled away the ice and snow to make room for the roaster ...


Mick, here I was...
waiting to see photos...
of your faithful Hottop...
sitting on a beautiful red cart...
with its casters resting on skis...
ready to be pushed through the door...
onto a snow laden patio.
homeroasters.org/php/images/smiley/roflmao.gif
Ciel
Ciel... seeking Heaven in my cup with ................................................................................................................. EXPOBAR Brewtus II - MAZZER Mini E - MAHLK�NIG Vario - GeneCafe - RAF-1 Extreme (Modified B-2 HOTTOP) - BellaTaiwan XJ-101
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