Induction heating element

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Gregredic

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I am thinking about boiling with electricity. Does anyone know much about induction heating element's? I have been flirting with the idea of using one of those along with a heat stick. Does anyone out there have any experience/knowledge on doing this? Does anyone know what kind of plug these things have on them? I will mostlikely be using a 220v. I am pretty much going into this blindly at this point. About the only thing I do know is that I will have to have a SS pot, as an aluminium pot will not work.
 
I've read a bit about induction stoves for kitchens and learned 3 points: They are more efficient than traditional electric stoves b/c all energy is converted to heating the pot up. There is a safety benefit in that the cook surface remains cool to the touch. Thirdly, though, they are ridiculously expensive because of the high voltage circuit and controls, plus the propriety cookware. I've never used one, but they seem far too expensive to for a couple of small benefits over a traditional way of heating water.
 
Here are some general Boiling With Electric links:

http://powersbrewery.home.comcast.net/~powersbrewery/hlt.html
http://www.bodensatz.com/article.php?story=20031026072427120
http://btracy.com/hot_liquor_tank.htm
http://www.brewing.schmidt-house.com/ElectricKettle.htm
http://home.chattanooga.net/~cdp/boilnew/boilnew.htm

Sorry, I don't know much specifically about induction elements, but the above should at least be good reference as you progress. :)

Edit: Been reading a bit... I would worry about the thickness of your kettle. You didn't indicate if this is for 5 gallon batches, or much larger.... A good thick-gauge S/S kettle will set you back a couple hundred, and that's excluding the cost of an induction stove itself, which appears to be well in the thousands of dollars. If you've got other good reasons to invest in one (cook a lot, current stove is dying anyways, etc etc) then perhaps it would be worth your money... but my gut reaction is that it's too new, too pricey, too much "tech" for our low-tech field.

After all, $3k could buy you all the parts to assemble one HELL of an Electric-based Brutus 10 system.
 
Could be interesting. I'll toss out the obligatory "Buyer beware" due to the (insanely?) low price of the unit and the Engrish prevalent throughout the ad. But Hey. You could be onto something. :)
 
Guys that thing is a steal! After all it has "Self-protection form being destroyed by thundering " I mean really, that just says it all.
 
The bottom of your pot MUST be perfectly flat for induction stoves or their efficiency is greatly reduced. I don't know about you but every pot/pan I have rocks and wiggles a little on the stove top.

John
 
here is the rub with Induction. It is a magnet that excites the atoms in the pot. For this to work your pot must be ferrous. Meaning the pot must be iron. Induction ranges will not work on Stainless or aluminum.


John
 
I had read at least one site that claimed S/S would work. I do not know for sure. Magnets stick to S/S, does that mean it is (at least somewhat) ferrous?

(Sorry, I don't know jack **** about metallurgy :drunk: )

I wonder how much an iron 15gal kettle would cost....... or weigh...... *shudder*
 
Everything I have read says that and induction heating element will in fact work with SS, but obviously will not work with alum.
 
I have a crappy stove that is unable to boil 5 gallons. I am looking at an induction solution. I will post here what I find.
 
I found my solution however its not an induction plate. I bought a stainless steel 30l pot from Austin Brewers website. Its 15 inches across and fits on 2 burners, its 13 inches deep. While not an induction plates it was less money and I know it will work. Plus it has 2 holes in it already one for a ball valve and one for a thermometer.
 
Man, I missed this thread twice:drunk: I think I may be the only one on HBT that uses induction cookers. I love them.

Yes they work with SOME stainless steel pots, not most though. We bought our first unit at a cooking store and paid ~$200. Of course then we had to buy some more cookware as my favorite SS pots weren't ferrous enough. We hunted a long time for a pasta pot that wasn't $$$$$. We used to go to kitchen stores and grab a fridge magnet to check the pots with. I've learned where to go now for pots that are relatively inexpensive.

One day we were in our local Target store and were checking out the clearance sections at the ends of the aisles and we saw two induction cookers for $35 each. Needless to say they both immediately went into our cart. One nice feature is that they are extremely portable. All you need is a 110 V outlet. It is nice in the summer to cook outside and not heat up the house. Particularly for things like boiling pasta. They are a blast to cook with. It is very similar to gas. Instant heat when you want it and instantly off when you want it. Extremely uniform heating in the bottom of the pot. They do draw a fair bit of power. You can't operate it on the same circuit as a microwave (in use) of a airconditioner.

Now my units don't have enough power to boil 6.5 gal. of wort. I use propane for that. I use one two heat my mash tun, and one to heat my hot liqour pot. They work fabulously for this. Step mashes are a breeze. I use the aluminized bubble wrap for insulation and do not have to worry about melting it. It is a very uniform heating so scorching is a non issue.
 
I found my solution however its not an induction plate. I bought a stainless steel 30l pot from Austin Brewers website. Its 15 inches across and fits on 2 burners, its 13 inches deep. While not an induction plates it was less money and I know it will work. Plus it has 2 holes in it already one for a ball valve and one for a thermometer.

yeah...Im going to do the same thing...get a big pot that will cover 2 stove eyes. Im thinking about modifying an old stove so that I can get it resting on 4 at once.

Do you have a link to the pot you bought?
 
yeah...Im going to do the same thing...get a big pot that will cover 2 stove eyes. Im thinking about modifying an old stove so that I can get it resting on 4 at once.

Do you have a link to the pot you bought?

Yes I do. Now I won this on the their eBay auction page. They have an ebay store as well. It came with a ball valve and no thermometer. I won it at $136 bucks, plus $6.99 shipping. I think it was a good deal. :D

Austin Homebrew Supply
 
I was just looking into induction cooking. I see some of these burners are selling for under $200. However, finding information on their BTU equivalency is very difficult. Too bad the MC-3500 is $1600+ CookTek® Induction Cooktops it puts out the equivalent of 31,000 BTU. Then again, the MC-1800 ($160) would probably work well, it puts out 1600 BTU and you could insulate your pot.

My real worry with one of these is how many years do they last? I have read a few stories about them losing efficiency after a year or two.

Anyone have any experience? pjj2ba - how have your induction burners faired over the years?


- M

PS: Sorry for digging up an old thread.
 
here is the rub with Induction. It is a magnet that excites the atoms in the pot. For this to work your pot must be ferrous. Meaning the pot must be iron. Induction ranges will not work on Stainless or aluminum.


John

Just thought I'd clear this up a little bit. First, ferrous does not mean iron, it means containing iron. Nothing you purchase anywhere will just be iron. Steel is (very simply) an alloy of iron and carbon. Even your cast iron pans or anything that is called cast iron is just steel with a high carbon content that was named cast iron because it is easy to cast. Stainless steel is (very simply again) steel that has also had chromium added to get the corrosion resistance properties.

Now on to this working on induction heaters. Because induction heaters work by oscillating a magnetic field, only vessels which respond to magnetism will work with them. This does not preclude stainless. Depending on the iron content of stainless steel it may or may not be magnetic enough to work with an induction cooker. Like was said above, just take a magnet and see if it will attract.
 
My induction cookers are still working like champs. The ceramic plate on our oldest unit (~8 yrs old) has come unglued but that isn't a problem, I just have to be carefull when picking it up. I pushed the limits of it with a 10 gal batch of IPA. Had my 40 qt mash tun filled to the brim. It weighed so much it pushed the cover down so it hit the fan and made a terrible racket. My mash tun is a little wider than the cooker so I rigged up some wood strips to take much of the pressure off the cook surface.

Still loving them!
 
Awesome, thank you for the input pjj2ba. Do you know what wattage the ones you have are? Or what their BTU equivalency is? About how long does it take to boil up 5 gallons? I am really thinking of going this way so I don't have to always do my cooking on the stove type. GLW would adore me for that and be totally behind spending a reasonable sum of money on it [under $500].
 
I think they are 1400 or 1600 watts. I don't know how long it would take to get 5 gal to a boil. I tried 6 gal once and it only made it to a simmer. I boil with propane. I do know 3 gal of tomato sauce will boil just fine. if you are doing less than 5 gal batches you should be fine.

I do lots of step mashes and with a typical 8.5 lb grain bill plus 3 gal of water, it heats up at about 1 F per minute.
 
For anyone curious, here is a Watts to BTU converter: Watts to Btus (IT)/Hour Conversion Calculator

Someone suggested the #SR1151 model to me: sr1151-1262f-1 However, it is 1,500W which is equiv to 5,100 BTU .. which seems like it would take forever to get 5gal to a boil.

However, BTUs on gas are hampered by a low efficiency - about 50%. Whereas induction is 85-90% efficient (depending on who you ask). So, a little math to appease the beer gods:

BTUs/hr = lbs water * temperature rise
8.3 lbs water / gallon
212F boiling - 70F starting = 142 F rise

Let's say we start at 6.5 gallons for a 5 gallon batch. So:
8.3lbs water / gallon * 6.5 gallons * 142F = 7,660 BTUs to boil in 1 hour.

Now, assuming 50% efficiency on a gas burner (and that is high, they are usually rated at 30%) means 7,660/50% = 15,321 BTU's to boil in 1 hour at 50% or 25,536 BTU's at 30% efficiency.

While induction is 90% efficient. So 7,660/90% = 8,512 BTUs to boil in one hour at 90% or 9,012 BTUs at 85% efficiency.

Okay, that is a huge difference [thinking outloud with fingers].

So, I need between an 8,500 and 9,000 BTU induction burner to boil 6.5 gallons within a reasonable time - and probably up to 12,000 BTU if counting for heat loss. So, at least 2,500W burner.

Now, Menu System (Swedish: :: MENU SYSTEM :: Induktionsherde - Induktionskochgeräte) does put out a standalone induction hob that puts out 6kW (6,000W) which is 20,472 BTUs. Using my calculations above, that hob should bring things to a boil in around 30 minutes.

But, what happens when I move to 10 gallons? That's 8.3*10*142=11,786 BTU's; and let's say 80% efficiency [the Menu System burner is rated 50-90%] then 14,732. So, full boil in about 45 minutes. I could live with that.

Anyone else have any thoughts on this?
 
What kind of prices are these units? The bigger ones I've seen have been quite expensive. I'd love to go all induction. Of course then I'd have to buy a magnetic boil pot too.
 
Sunpentown's hobs that fit the bill appear to be discontinued, but if you can find them they appear to run $300-$600.

I haven ot heard back from Menu System's yet, but I am expecting between $800-$2000 USD, prior to conversion or anything else. However, sometimes things come out as cheaper than expected, so who knows. The main problem is that Menu System is not UL approved.

As for magnetic boil pot. I told SWMBO that I wanted to pay the $20 more for the really good boil pot :\ She insisted I go cheaper ... which is the pot that has led me to the problems I am having now. As in, it loses too much heat to boil properly on my 16,000 BTU burner (thus I need to insulate it) and, oh yes, it isn't magnetic - at all. Whatever type of Stainless Steel it is, it's cheap. I ran to the shop and tested the other one [that had been on sale at the time, and is now $100 more expensive than it was, yay] and it loves the magnets. Oh well, just one more cost!
 
Sorry for jumping in here, I'll admit I have not read the total thread. But I have the Sr1881, it is 1200W max, I have not tried to boil more than 2 gallons on it But it worked well for that. Have you considered the weight problem of having 6 gallon in a pot on this unit?

I have thought about trying it but don't have a magnetic pot that size, but have wondered if I did, would it hold up and function with that much weight on it?
 
Have you considered the weight problem of having 6 gallon in a pot on this unit?

I have thought about trying it but don't have a magnetic pot that size, but have wondered if I did, would it hold up and function with that much weight on it?

I've pushed mine to the limit and had the top push down onto the fan requiring me to quick rig up some supports under the sides of the mash tun. This was for a 10 gal batch of IPA so it would have been ~24 lbs grain plus 5 gal water plus a pretty heavy duty pot. I just did another 10 gal batch, but this one only had 19 lbs of grain and that was not a problem. This will vary of course from manufacturer to manufacturer. I'm thinking about installing some permanent supports to take a bit of the load off the top of the unit (my pot goes over the edges).
 
Thanks Pjj2ba,

Sorry for making you repeat your self, I just went back through this thread.

The reason I bought the induction cook top was to set up a direct fire Mash,and that appears to be what you are doing. So I have one more question to you:

Do you set the temp on the Cook top to your mash temp? or do you just turn it to high, and turn it off when you hit your desired mash temp?

I have not started experimenting with this yet, and am just using it to make starters, but you might have revived this experiment.
 
Supposedly the #SR1151 can hold up to 100 pounds. However, the #SR1881 is supposedly limited to 30 pounds.

6.5 pounds = 53.95 pounds.
 
Let me dispel some misinformation about induction. I sell restaurant equipment and one of the things I demo is a single burner induction hotplate.

It is not like a glass top electric burner, your pot does not have to be flat or even for them to work. I cooked a quesadilla in a pan on top of a folded up tshirt.

As stated above, any magnetic pot will work, however, the more base the metal the better. It will work well with 18/0 SS but 18/10 does not work due to the increased nickel and chrome content. Carbon steel and cast iron work great. Aluminum and copper are out.

1800 watts @110v is the minumum you should attempt, but I think that most pots above 20 quarts will be bigger around than the sweet spot of the burner thereby decreasing efficiency. You can get an import version in the mid $200's.
Word on the street: a 3500 watt 220v hotplate will boil a half gallon of water in 50 seconds.

For research sake, Vollrath makes a 3 ply pot that screams on induction. A few imports like Update make a good single wall aluminum-clad bottom pot that work well and you should be able to find up to a 60 quart for less than $200.

The magnet test is for real. If you are interested in this technology, take a magnet with you when you shop for pots. If it sticks well it will work.
 
For research sake, Vollrath makes a 3 ply pot that screams on induction. A few imports like Update make a good single wall aluminum-clad bottom pot that work well and you should be able to find up to a 60 quart for less than $200.

The magnet test is for real. If you are interested in this technology, take a magnet with you when you shop for pots. If it sticks well it will work.

My mash tun is from Volrath - it's a great pot! Most of the pans I've bought to use to cook with are from Update and I love cooking with them.

Could you reveal your source for that data. This Oregon State University Fuel use Calculator says that the Heat Efficiency of Natural Gas is 78%

I'm not sure what his source is, but the point he is making is that very little heat is lost. The pot is what heats up, not the element, so the only heat transfer is pot to contents. With Natural Gas, it goes flame to pot to contents. A lot of heat is lost to the air. If you are just heating air, like to heat a house, then you can get 78% efficiency. It is going to be much lower for cooking though.
 
The efficiency of natural gas as a fuel is higher than its efficiency when used on a cooktop although its not quite as low as 30%. Much energy is wasted when using it to cook. You can tell by how hot your kitchen gets. Induction is 80-90%
 
@Sawdustguy: The efficiency is lower than ambient heat (as others have explained). Natural gas cooking is generally rated between 30% and 40% efficiency - I went with the low end of the calculations on everything. When cooking with gas a fair amount of the heat is reflected down and away from the pot. When cooking with induction it is the pot that warms up and it only loses heat that is not absorbed [heat transfer flows in the most efficient direction - which is often whatever is coldest first]. As a result, direct heating of any type is more efficient than gas - except for ambient results, then gas is king. That said, I love using gas.

As for sources on that, there are several, most of which are tests done by induction hob producers (which is why I underguessed their typical estimate of 90% efficiency). However, wikipedia also has information on it. I do not have a direct link to an actual report by an independent agency to back me up - however, experience and physics match with the estimates I have seen.

As for 440v power on the Menu System 6kW unit, that is true, but the power unit can be converted -- I have been informed by an induction hob supplier here in the States (who does not provide Menu System themselves) that they have seen Menu System hobs used in U.S. kitchen, including standalone units, that have had a converter wired in by Menu System. The main thing here is to see if your residential power supply can actually put out 6kW of power, if it can't then the hob will draw too much power, pop a breaker, or just not work. 1 Watt = 1 Volt * 1 Amp. So x Amps = Watts/Volts = 6,000W/110V = 54A. The grid in the U.S. provides 220V/200A = 44,000W. I live in a older home with a 110V / 100A drop. That puts me well above the 54A need to reach 6kW. Therefore, instead, the trick is to get the unit converted - or, alternatively, buy an external conversion unit. This is doable using a step up transformer (to 440v it's two step up transformers, but it is doable). That said, it's doable.

----

@northernlad: You sir are a fountain of information. Thank you. So, it looks like I will probably have to go with the Menu System or another European model. One thought, perhaps I could find a unit with enough wattage, and then use a rack to suspend the pot - so it is just barely resting on the surface but the rack distributes all of the weight away from the hob. From what you said, it seems like there would be no problem with doing this? I could easily build a split C stand that holds onto the rim and handles of a large pot...

-----

Of course, the other option, would be to build a coil induction heater and then drop the pot into it. That would heat not just the bottom but the sidewalls, which would definitely move things to a boil. Albeit, it would be a bit ungainly - and I haven't played seriously with electricity like that in years; I wonder if my electrician cousin would give me a hand. I wonder what would happen if I put the heatsink under the pan as yet another heatsource, but put a fan across its bottom to keep the unit cool. Anyway, people have been making their own induction heaters: DIY Induction Heater - Hacked Gadgets - DIY Tech Blog I'm sure with a little bit of industriousness such a thing could be made for a pot ;). That is, assuming I can't find a decent hob at a good price.
 
As for 440v power on the Menu System 6kW unit, that is true, but the power unit can be converted -- I have been informed by an induction hob supplier here in the States (who does not provide Menu System themselves) that they have seen Menu System hobs used in U.S. kitchen, including standalone units, that have had a converter wired in by Menu System. The main thing here is to see if your residential power supply can actually put out 6kW of power, if it can't then the hob will draw too much power, pop a breaker, or just not work. 1 Watt = 1 Volt * 1 Amp. So x Amps = Watts/Volts = 6,000W/110V = 54A. The grid in the U.S. provides 220V/200A = 44,000W. I live in a older home with a 110V / 100A drop. That puts me well above the 54A need to reach 6kW. Therefore, instead, the trick is to get the unit converted - or, alternatively, buy an external conversion unit. This is doable using a step up transformer (to 440v it's two step up transformers, but it is doable). That said, it's doable.

Actually you need to add 3 or 4 amps more if the unit could be run on 110 VAC. The pdf says that the device itself can be expected to dissapate between 300 to 400 watts of heat (you can see the large heatsink with fans in the picture in the pdf file). This has to accounted for also because the unit itself is not 100% efficient in delivering 6kW to the load. Another thing to consider is that the unit is speced at 3 x 400 to 440. I wonder if they mean 440vac 3 phase (common here in the US for industrial machinery). If that is true a simple transformer will not work. Getting this unit to work in someone's home is a stretch at best.
 
Yeah, I think trying to convert a 440v unit to 220v woulld be more work than necessary and additional money. Getting a commercial unit wired 208/240v versus 115v is generally no charge but 440v is always an upcharge. So, you would be paying extra for the high voltage and then pay for a converter to lose the big pipe.
i would investigate a 208/240v 3500 watt commercial induction burner from Vollrath or Cooktek. Both make an excellent product and should be enough for full boils. The challange will always be whether the size of the cooking surface is the same the diameter as your pot. If your pot is bigger your efficiency goes down.
If you would like specific product notes and cut sheets for the burners let me know and I will send them from work.
And, yes a full boil is almost assuredly too heavy for the burner, but I will check weight limits.
 
@northernlad: If you could send me those specs it would be great.

@Sawdustguy: I interpret their 6kW as 100% power; not max actual power. Am I wrong in this? That is the assumption I used in my earlier calculations that took efficiency into account. On a unit like that, if it was only 80% efficient, you would be losing about 1200W. However, I admit, I am not an electrician so could be wrong. And, they do mean 440vac 3 phase. As I said earlier, I have been informed [and had it confirmed today by Menu System] that they can change the power unit to work in a U.S. residential setting. Albeit, they won't be able to give me a price estimate for a few more days.

So, while it might be a stretch, what does it hurt to look into it? Am I going to be arrested by the U.S. Overlords of Power Decency for exploring my options? :p
 
So, while it might be a stretch, what does it hurt to look into it? Am I going to be arrested by the U.S. Overlords of Power Decency for exploring my options? :p

It doesn't hurt at all. I just think there are more practical and less expensive solutions for heating a kettle. Simply mounting an 5500 watt electric heating element into a kettle is much less expensive and pretty efficient also.

If you read the pdf it does state that the unit itself does generate 300 to 400 watts of heat. That means to generate 6000 watts it uses a minimum of 6400 watts. There may be other losses also.
 
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