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daniboy503
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· 04/05/2020 10:37 PM
i need wiring modification for westbend poppery I that has AC fan with rotary dimmer and AC fan speed control switches Thank you!

allenb
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· 04/02/2020 4:50 AM
Morning Ed, I haven't done any green coffee hoarding yet but am hoping the supplies don't end up like the toilet paper isles!

snwcmpr
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· 03/31/2020 2:53 PM
Hey Ed. Thanks. roar

homeroaster
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· 03/31/2020 11:21 AM
Hey quarantined home roasters! I hope you have great coffee! If they have a run on coffee, I hope you're set with your great home roast! Find me on Facebook! Ed Needham

snwcmpr
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· 03/25/2020 11:49 AM
New Rochelle in the news. I think of you every time I hear it. ... Please stay safe.

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Enhancing My HotTop (4 of 5) - Filtering, Smoking, and Venting
ciel-007
This is the 4th post in a series about my HotTop. Earlier topics covered:
1- Potential HotTop annoyances,
2- Monitoring Beam Mass Temperature, and
3- Handling Chaff.

This post looks at ways to improve the roaster regarding filtering, smoking and venting issues. My HotTop can roast 350 grams (3/4 lbs) of green beans well beyond Second Crack. Roasting that much coffee to such high temperatures creates SMOKE – lots of SMOKE. As a result, filtering, smoking and venting issues are not trivial challenges for many HotTop owners.

Filter Costs and How to Reduce them:
The HotTop has two filters (one Top Filter and one Rear Filter) that are designed to capture the smoke particles created during roasting. The current design calls for the periodic replacement of those filters. HotTopUSA sells the replacement Rear Filter for $10 (+ $6.25 shipping). HotTop USA also sells the replacement Top Filter for the same amount. For those who roast a lot of coffee, filter replacement costs may be a significant expense.

There are a couple of ways to reduce, or possibly eliminate those costs; Randy Glass was the first to talk about how to do this.
Solution 1: Simply wash the filters when they get dirty:
http://www.frcndigital.com/coffee/HOT...FAQ.html#6
Solution 2: Replace the Back Filter with a permanent metal filter:
http://www.frcndigital.com/coffee/Hot...ilter.html

Here is an example of how I reduced filter costs using a variation of Randy’s second solution. The photos below show that I am using 120mm metal filter with a twist. Before pushing the metal filter into the HotTop’s plastic filter holder, I first slip a piece of paper towel underneath the filter. The paper towel can be easily cut to size; this provides much finer filtering than a metal screen does when used alone. The paper towel also offers a bit of resistance to the air flow, similar to the original HotTop filter. If you try this, check to see if your paper towel has two plies. If so, the plies can usually be split part with ease giving you the ability to test which thickness works best for you. In my experiments, the paper towel did a good job in capturing particles (note the stains in the second photo). The risk of fire was not an issue for me because the heat from the exhaust fumes remained well below the temperature required for the spontaneous combustion of paper.

Although the HotTop filters help to reduce smoke during roasting, they do not eliminate it.
ciel-007 attached the following images:
fvs-f-2.jpg fvs-f-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
 
ciel-007
Smoking and Negative Pressure (NP) in the Chamber:

The components of the roasting chamber on the HotTop fit together nicely; however, fitting is not exact. As a result, it is not unusual to notice smoke appearing as the roast progresses. Most notable is the smoke escaping from the bean loading chute and the top filter, especially when the cooling fan is at the lowest speed. Further, smoking tends to increase as the filters become clogged, or when chaff accumulates in the roasting chamber. I did consider making a silicone seal to fit around the bean chute cover; however, I changed my mind once I realized that there were deeper design issues affecting the flow of air through the roasting chamber.

Smoking issues in the HotTop appear to be linked to varying levels of Negative Pressure (NP) inside the roasting chamber. When the large cooling fan is turned ON, that creates some NP by sucking air from inside the chamber. This NP should typically be affected by at least four factors: the fan speed, the condition of the top filter, the condition of the back filter, and the size of the vent holes allowing fresh air to enter the roaster from the back. During roasting, NP in the chamber will obviously be weak (encouraging smoking) when the fan is at a low speed, and/or when the filters are dirty. On the other hand, NP in the chamber will be high (resulting in little or no smoking) when both filters are clean, and when the fan is at high speed. Theoretically, NP should be increased even further by restricting air flow entering the roaster through the vent openings on the back.

The photo below shows a total of 24 vent openings on the backside of the roaster. I conducted trials that involved obstructing some or all the vents (using fiberglass wool) in order to increase NP in the chamber. By doing so, my objective was to increase NP and thus reduce the amount of smoke escaping from the bean chute cover. As it turns out, blocking those vents actually did reduce smoking, especially in the earlier stages of the roast (before Second Crack). However, as the smoldering beans advanced passed Second Crack, I discovered that bean chute smoking could not be prevented by merely obstructing the back vents to increase NP. At advanced stages (approaching French Roast), I found that the only way to stop bean chute smoking was to actually remove the back filter. Obviously, removing the back filter is self-defeating because that causes even more smoke to spill into the room. Based on such experiments, I am inclined to conclude that smoking annoyances cannot be resolved satisfactorily on the HotTop roaster, unless a more advanced course of action is considered.
ciel-007 attached the following image:
fsv-s-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
 
ciel-007
Outside Venting:

The above trials lead me to conclude that it is not feasible to roast over 300 grams of green beans beyond Second Crack indoors without some outside venting. My conclusion is based on the realization that the HotTop’s back filter (currently made of fine porosity paper), may be too restrictive to allow adequate air flow at advanced roasting levels. (This conclusion might be invalidated if a more advanced filtering device, perhaps an electrostatic precipitator filter, was available for the HotTop).

The most common method of venting outside is to use the range hood in the kitchen. Some roasters are easier to vent than others. For example, one attractive feature on my Gene Café roaster is that it has an 80mm fitting on top of the large chaff collector; that allows one to easily attach a vent pipe to channel smoke towards an exhaust hood, a downdraft, or perhaps through an outside wall. Unfortunately, the HotTop does not come equipped with a similar vent fitting. However, it is entirely possible to build one.

The photos below show an example of a vent system that has been custom built to fit a HotTop roaster. A square cap can be made to fit over the roaster’s fan housing. That cap can then be attached to the HotTop and connected to a flexible exhaust duct. Although I have not tested such a system, it would seem capable of handling the smoking issues identified above. With such a venting system, it would now be possible to remove the back filter from the HotTop in order to maximize fan effectiveness; removing the back filter should increase the Negative Pressure inside the roasting chamber to a level sufficient to completely eliminate smoking. These photos appeared in an eBay auction a few months ago. The design is straightforward. If you don’t see it on sale on eBay, it could be an interesting weekend project for a HomeRoaster to complete.
ciel-007 attached the following images:
fsv-v-2.jpg fsv-v-1.jpg

Edited by ciel-007 on 10/27/2012 3:33 PM
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
 
ciel-007
Ciel’s Roast & Grill

During a 12 month period, the temperature at my home, here in the Nation’s Capital, ranges from below -30C to above +30C. As a result, there are times when roasting or grilling outside is not an option. This annoyance led me to convert a portion of my work-shop into a play-corner.

The corner initially allowed me to grill and smoke indoors with my Kamado. The walls are protected with galvanized sheet metal. The 900 CFM exhaust fan does the job of expelling massive amounts of smoke coming from the Kamado during grilling.

A few months ago, I added a small shelf next to the Kamado. Initially, it was used to roast coffee with my Gene Cafe roaster. Since, it has welcomed the likes of HotTop models KN8828P-2 and KN8828B-2. The shelf holds the roaster and BMT thermometer at eye level for easy monitoring of profiles. When I’m finished roasting and it’s time to grill, the roaster conveniently slides up and out of the way, and the Kamado takes center stage.

If you’re serious about coffee, I figure your roaster deserves its own special corner…. Welcome to Ciel’s Roast & Grill !
ciel-007 attached the following images:
fsv-c-2.jpg fsv-c-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
 
smico
First lavitating coffee roaster ever...

Great articles, as usual, Ciel. I will add few pictures of my setup when I find some time.
Hottop B2 + HTC, Cremina 83, OE Pharos, Brewtus IIIR, Baratza Vario
 
ronsil

Quote

ciel-007 wrote: I reduced filter costs using a variation of Randy’s second solution. The photos below show that I am using 120mm metal filter with a twist. Before pushing the metal filter into the HotTop’s plastic filter holder, I first slip a piece of paper towel underneath the filter. T.


I purchased 2 x metal filters some time ago & have been experimenting how to best use them.

Your idea looks like the perfect answer. I've started using good quality kitchen roll & changing it every 10 uses. It seems to give the same result as the HT rear filters.

As you say use with care but the temperature in the filter area is no where near the combustion point for paper. Of course it looks scorched but that's the coffee residues
Ron
 
JETROASTER
I really like the telescopic shelf! ....I'll be borrowing that one.
Really nice workspace!
Thanks,-Scott

Q;) What maintains the uplock position?
 
snwcmpr
I use Urnex - Full Circle Coffee Equipment Wash ... http://www.fullcirclebrand.com/produc...ment-wash/.
I do not take the filter apart, I just soak it in a glass pan with a mild solution. Probably 1 tsp per liter.
Then rinse and soak in plain water and air dry till I replace the one i am using. I get 20 roasts, then change the filter.
I have been dong this a year and a half.
I never had to disassemble the filter.
I do the same with the top filter, but not nearly as often.

Ken
--------------
Backwoods Roaster
"I wish I could taste as well as I wish I could roast."

As Abraham Lincoln said "Do not trust everything you read on the internet".
 
ciel-007

Quote

freshbeans wrote:

I really like the telescopic shelf! ... What maintains the uplock position?


Thanks Scott. When I slide the shelf upwards it will automatically lock into position with a spring loaded latch. Here is a close-up of the undershelf showing the latch doing its job.
ciel-007 attached the following image:
spring_latch_hro.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
 
ciel-007

Quote

smico wrote:

Great articles, as usual, Ciel. I will add few pictures of my setup when I find some time.


Thanks Miroslav. I look forward to seeing your setup.
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
 
fore
Ciel, did you ever get a chance to see if that vent attached to the HT did an effective job of handling the smoke?...or know anyone who tried this?
 
ciel-007

Quote

fore wrote:

Ciel, did you ever get a chance to see if that vent attached to the HT did an effective job of handling the smoke?...or know anyone who tried this?


Fore, I have never gotten around to personally testing the "Outside Venting" mod; perhaps other Hottop owners here at HRO have?

http://homeroasters.org/php/forum/vie...post_39735

However, based on what I've discovered from numerous other experiments on my Hottops, I am confident that the outside vent mod would yield satisfactory results.

Happy roasting this Winter, 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
 
smico
It looks like I have forgotten to show my setup featuring cardboard chimney and kitchen range hood vented outside.
Better late than never...
smico attached the following image:
img-20120310-00115.jpg

Hottop B2 + HTC, Cremina 83, OE Pharos, Brewtus IIIR, Baratza Vario
 
ciel-007

Quote

smico wrote:

It looks like I have forgotten to show my setup featuring cardboard chimney and kitchen range hood vented outside.


Miroslav, thanks for posting the photo. I really like your ingenious chimney.
I look forward to seeing many more of your great photos.
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
 
allenb

Quote

smico wrote:

It looks like I have forgotten to show my setup featuring cardboard chimney and kitchen range hood vented outside.
Better late than never...


You've got one ultra cool setup and I love your high tech vent hood! I've got a question for you. Are you the only one using the washer and dryer?

Allen
1/2 lb and 1 lb drum, Siemens Sirocco fluidbed, presspot, chemex, cajun biggin brewer from the backwoods of Louisiana
 
smico
Haha... Thanks Ciel. I do know how to make something out of nothing. It probably comes from times when I didn't have much...

Yes Allen, I should have said also featuring unplugged freezer full of green coffee beans, and washer waiting for my next trip to Germany to buy ball bearrings...
Hottop B2 + HTC, Cremina 83, OE Pharos, Brewtus IIIR, Baratza Vario
 
BarryR

Quote

smico wrote:

It looks like I have forgotten to show my setup featuring cardboard chimney and kitchen range hood vented outside.
Better late than never...


I've just about decided it's time to upgrade to a Hottop (B). I even have someone who probably wants to buy my Behmor so the timing's perfect.

My main concern is the smoke. I have a strong vent hood in the kitchen (looks just like yours, but connects to an external blower (I forgot how many cfm, but it's pretty strong / not just for decoration). With a set up like this + your cardboard chimney, how good should the smoke control be? How bad is it when the beans dump (I usually roast to FC, sometimes FC+, especially for espresso, and almost never beyond FC+).
 
BarryR
I could hold out no longer.
Pulled the trigger today and ordered it from Roastmaters.com.
I'm in MA so it only takes about a day to ship. Should get it between Tuesday and Thursday, I'd think.

Pretty psyched. I think I'll be building a cardboard chimney.
Any chance of it combusting? (I'd think not but...)
 
smico
Barry,

Our member fore has been using this solution in his kitchen, so you might want to ask him for his experiences. I roast up to 10 back to back roasts in my garage on regular basis, and smoke is not an issue.

I don't have slightest concern about the combustion of the cardboard chimney. Some people use Bounty like paper towels as filters without any issue.

Congratulations for your new roaster. I hope that you will be as happy with your Hottop B as I am with mine.

Cheers,

Miroslav
Hottop B2 + HTC, Cremina 83, OE Pharos, Brewtus IIIR, Baratza Vario
 
BarryR
Got the Hottop KN-8828-B2-K today and roasted 250 gm of a Guat Huehue (from GCBC).

I sort of followed RGs B2K instructions from the Hottop website.

Certainly more smoke than the Behmor (especially at bean release) but not way worse and it will certainly be manageable in my house.

Since I think a lot of the smoke is on release, a cardboard chimney might not work so I may try some cardboard "baffles" hanging down from my vent hood since my vent hood is pretty high. This may help capture escaping smoke.

I'll post a separate entry about my first roast experience and questions, but so far I'm pretty impressed. Let's see what happens when I taste the product.

(I think I'll make a cup tomorrow morning, but that will only be a 12 hour rest).
 
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