Possible Electric build with silicone heat mats

[Shane23]

I'm in the begining stages of planning a electric build and I got two Wattco Slicone rubber sheets that can reach 450 degrees for free. So I thought I would use one for the MLT and one for the boil kettle. The plan is to wrap the heaters around the keggles so the entire walls will be heated. I was thinking it would be more efficient then using regular elements and I wouldn't need a RIMS or HERMS to keep the mash at temp.

Has anyone seen a system like this or can think of any issues with this plan?

This is a link to the heaters I will be using:
http://www.wattco.com/silicone-heaters.html

 

[fifelee]

I used those in a former job. Never heard of them being used in brewing but it seems like it would work. Would be easy to test, so give it a go. Would love to hear the results.

 

[durban]

It can be done, I know a guy that has a 30qt kettle that uses 3 silicone heating pads from McMaster. If I remember correctly, it'll bring 5 gal to a boil in about 1/2 hour. He did have it listed on ebay, but IDK if its still there.

 

[vballdrummer]

I guess it depends on the voltage and wattage of the particular mats you have. The spec says up to 480V, which is not going to be available in your home. And if they are rated at 480V, running them at 240V will decrease the wattage by 75%. But like fifelee said, easy enough to test! Let us know.

 

[wrench]

If they don't work for the actual brew, they'd certainly make great warming belts for fermenters.

 

[kal]

Here's the link at Mcmaster Carr:

http://www.mcmaster.com/#heat-blankets/=bnozzp

These are interesting. The highest wattage is 2160W so you could use it to boil but only a small (possibly 5 gallon) kettle. $584 however which makes them somewhat expensive compared to $50-75 or so to integrate a 5500W hot water heater element (as is done by many electric brewers).

Since yours were free, why not try them of course.

Kal

 

[Shane23]

The guy I got the mats from uses them to heat a press that runs from 165 to 150 degrees 8 hours a day. He said if I ran them at 120v they could hit about 175 and at 220v they would easily go over 200.

Would the heat source coming from the sides change the physics of the boil?

Any ideas of what kind of insulation to put around the outside?
I'll wrap the heater around the kettle, then wrap a metal strip around the mat (completely covering the mat) to hold the mat tight against the kettle. Put insulation around that and seal it up. I need an insulation that can handle the direct heat without melting.

 

[kal]

Would the heat source coming from the sides change the physics of the boil?

Possibly, but not in any bad way. Boiling in commercial boil kettles is often with steam jackets that provides heat through the sides in the same manner. Just make sure that the heat source has wort on the other side of the kettle wall instead of air (ie: place the heat mats low enough).

Kal

 

[ajm163]

Seems like a bit of an old thread... Curious if you tried these out... If so how did they work out???

 

[Shane23]

Well unfortunately I haven't gotten to that stage of my brew stand build. Finding a keg for my mlt is next on the list so hopefully I will have it going soon.I've done some tests and I know the mat will work for the mlt running on just 120v. I don't think I'll end up trying it on a kettle for a while. As soon as I get it going I'll post soon pics tho

 

[mysobry]

Interested to this thread...
Trying to understand if you have enough power with 220V power supply to bring to boil my single vessel all in one (BIAB) 5gal system.
The idea behind is to have uniform heating in all the phases

I have a 35cm diameter kettle with 30cm height so I have a rectangular surface of around 100cm x 30cm plus a circular surface on the bottom of 35cm so you have In total 3000-3500cmq of heating surface
Is this enough with the power density of silicon rubber heater for mashing/boiling ?

Regards
Davide

 

[brewguyver]

If it didn't work for boiling, that would probably make a great HEX tube setup for either instant-on mash water or HERMS. They'd also beat the piss out of reptile heaters wrt to a germ chamber build. The only thing I'd be worried about is overheating and fire I the OP's kettle water level got too low.

So... how did it go?

 

[alien]

Would be great for wrapping around a RIMS tube I reckon.

 

[mysobry]

It’s an idea that I have since long time ago: use external silicon flexible heater band in order to mange the mashing and boiling process

The advantages are more than one, have uniform heating without scorching the worth with immersion heater, have an internal surface without any interference for whirpool, easy cleaning etc…

I don't konw if there have been progress so far but now the idea is a reality and prototype, I have requested some custome silicone heater to a specialized company and I have mounted on my BIAB pot
The bottom pud is around 800W @ 220V while the lateral band is 1700W
They are self-adhesive with special 3M glue and easy to install

First test are promising , I would like to run a full test from cold water to boiling logging time/power/temperature and share the result

stay tuned
Davide

 

[trboyden]

Good luck with your experiment! The idea with elements is that you are heating the water directly, therefore more efficient and quicker heating. That is the major benefit (as well as enhanced temperature control) versus external heat sources where you have to heat the vessel prior to heating the water/wort.

Your design should certainly work for mashing, but you have a watt shortage for boil applications (consider most electric setups use a 4500 - 5500 watt element). From 45 degree water, it takes my 4500 watt BoilCoil around 45 minutes to reach boiling. For my 5500 watt ripple elements it takes about 25 - 30 minutes to do the same. My pots are 15 gallon SS, typically boiling a volume of 7 or 8 gallons.

 

[kal]

For the mash you'd need to make sure you recirculate to ensure an even temperature.

Since you mentione BIAB, I'm assuming you're doing 5 gallon batches at most? Unfortunately the 2500W you have for the boil kettle isn't probably going to be enough, especially since you do not have all of the heat going directly into the kettle as the previous poster mentioned. Much of the heat will simply escape in the other direction.

The other thing I'd be concerned about is the fragility of the connection points when cleaning the kettles (the wires look easy to break off) not to mention getting the pads wet/difficulty in cleaning (a boil over would make a mess of the pads), and issues with having the glue eventually no longer hold/drying out.

Using a HERMS setup with indirect heating of the mash never causes scorching, nor is scorching a problem in the boil kettle with ULWD elements (many use higher density elements as well without issues). If scorching was a big issue, then we wouldn't have the tens of thousands of brewers using electric heating elements that we do today. Some of the professional brewers I've talked to (ex: WingMan Brewers, Tacoma WA) even tell that they have less caramelization since they switched to electric heating elements.

You can still get a whirlpool going with an element in the way from what I understand.

I'm still curious to hear your results however. Please do post! Good luck!

What did the pads cost you for one kettle?

Kal

 

[mysobry]

Good luck with your experiment! The idea with elements is that you are heating the water directly, therefore more efficient and quicker heating.

You are right the best efficnecy can be achived by immersione heating

That is the major benefit (as well as enhanced temperature control) versus external heat sources where you have to heat the vessel prior to heating the water/wort.

Not clear to me this point , in term of control you can apply the same strategy and systems (Typically PID/PWM with SSR)

Your design should certainly work for mashing, but you have a watt shortage for boil applications (consider most electric setups use a 4500 - 5500 watt element). From 45 degree water, it takes my 4500 watt BoilCoil around 45 minutes to reach boiling. For my 5500 watt ripple elements it takes about 25 - 30 minutes to do the same. My pots are 15 gallon SS, typically boiling a volume of 7 or 8 gallons.

Maybe in US everything is "big" but here in italy the maximum household power is 3KW and off course you can't use all for the electrical brewing pot.
Average power of EU brewing system is between 1.8 to 2.3 KW (braumeister, bielmeier..) for 20L batches

Indeed also a insulation of the external part could help a lot to increase efficiency and heat transfer to internal

I let you know my experimet result

Davide

 

[Weezy]

I've toiled over external electric elements as well. I use a 940W thermal wire to maintain mash temps, but its very inefficient for heating water to strike temps or boiling. A wire wrapped tight on a copper tube van work well for RIMS, and can be enough to step mash. But you have to remember that external elements are only going to be 33-50% efficient. You'll need 4500W+ just to get 2000W of heating power to the wort. It can be done but you'll be heating the room more than the beer. Your setup is 1500W, so your wort is seeing 500-750W.

 

[mysobry]

For the mash you'd need to make sure you recirculate to ensure an even temperature.

This is for sure Kal..the system is a BIAB with recirculation from bottom to top

Since you mentione BIAB, I'm assuming you're doing 5 gallon batches at most? Unfortunately the 2500W you have for the boil kettle isn't probably going to be enough, especially since you do not have all of the heat going directly into the kettle as the previous poster mentioned. Much of the heat will simply escape in the other direction.

Yes you are right the idea is to mange 5gal batches, not sure that 2,5KW is not enough for boiling…I had in the past (long time ago &#61514 may brewday with my glorious bielmeier pot that is 1.8Kw and indeed also the well known 20L speidel braumeister is not much more powerfull with heating coil of 2KW and no insulation !

The other thing I'd be concerned about is the fragility of the connection points when cleaning the kettles (the wires look easy to break off) not to mention getting the pads wet/difficulty in cleaning (a boil over would make a mess of the pads), and issues with having the glue eventually no longer hold/drying out.

This is good point ..indeed the wires are very flexible and well anchored and my idea is to use a power connector to the control unit in order to plug and unplug for vessel removal and cleaning. About wetting the external surface you are right and you must be very conscious unless you use some insulation/cover water proof (neoprene??)

Using a HERMS setup with indirect heating of the mash never causes scorching, nor is scorching a problem in the boil kettle with ULWD elements (many use higher density elements as well without issues). If scorching was a big issue, then we wouldn't have the tens of thousands of brewers using electric heating elements that we do today. Some of the professional brewers I've talked to (ex: WingMan Brewers, Tacoma WA) even tell that they have less caramelization since they switched to electric heating elements.

This is a matter of philosophy ..In HERMES systems you need at least two vessels and this is NOT my project requirements that is strictly all in one single vessel compact/light/easy to use and store. About scorching I can partially agree with you…is not a very big issue but the idea behind my solution is to have an ALTERNATIVE to the traditional brewing sustem (single vessel) with external heating helmet…I mention again Speidel Brumeister and Bielmeier that has 2Kw resistor on the bottom. Compared to that reference sytesm I assume that my heating is better…with some cons discussed above..but at the end of the day better.

You can still get a whirlpool going with an element in the way from what I understand.

Depending of the heating element type and placement whirpool and cleaning can be more difficult than a completely empty and clean vessel

I'm still curious to hear your results however. Please do post! Good luck!

What did the pads cost you for one kettle?

Kal

Sure I will keep you updated !

Davide

 

[mysobry]

I've toiled over external electric elements as well. I use a 940W thermal wire to maintain mash temps, but its very inefficient for heating water to strike temps or boiling. A wire wrapped tight on a copper tube van work well for RIMS, and can be enough to step mash. But you have to remember that external elements are only going to be 33-50% efficient. You'll need 4500W+ just to get 2000W of heating power to the wort. It can be done but you'll be heating the room more than the beer. Your setup is 1500W, so your wort is seeing 500-750W.

same answer than to other people complaining with the low efficiency

how does the two widespread systems work ??

BIELMEIER
http://www.bielmeier-hausgeraete.com/bielmeier-maische-und-sudkessel-edelstahl-040001-1

BRAUMEISTER
http://speidels-braumeister.de/shop/en/20-50-Litre-Braumeister/20-litre-Braumeister


they have maximum 2Kw heating coil on the bottom without any insulation and are used by thousands of HB

Davide

 

[trboyden]

You seem to think the debate is that we are saying it can't be done with 2000 watts. But no one is saying that. We're just saying it won't be efficient. You have to factor in all the math; starting water temperature, the differential between that temp and boiling temp, the volume of wort, how many watts you have, and time.

Also you are heating externally - those devices you mention use an element in the pot, therefore they are more efficient because they are just heating the water. They are also insulated. So they can get away with only 2000 watts. But it probably takes them at least 2 hours to get to boiling (and the instructions say they aren't necessarily able to get to 100*C - see page 4 in the manual). They are also designed for exactly 20L. Most US home brewers make a compromise and use 15 gallon pots so they can do 20L or 50L batches, so they size their elements for the larger batch size. Which means they can do a 20L batch in a shorter period of time.

Awhile ago I made up a calculator using Microsoft Excel to calculate how much time it would take to get wort to boiling. It's ballpark because it doesn't take into account external influences such as ambient temperature or the material of your pot/insulation factors, but I have found it to be pretty accurate. Here is the link to the file via my OneDrive account:

Electric Brewing Calculator

Cheers,

Tim

same answer than to other people complaining with the low efficiency

how does the two widespread systems work ??

BIELMEIER
http://www.bielmeier-hausgeraete.com/bielmeier-maische-und-sudkessel-edelstahl-040001-1

BRAUMEISTER
http://speidels-braumeister.de/shop/en/20-50-Litre-Braumeister/20-litre-Braumeister


they have maximum 2Kw heating coil on the bottom without any insulation and are used by thousands of HB

Davide

 

[Weezy]

You seem to think the debate is that we are saying it can't be done with 2000 watts. But no one is saying that.

I am saying that....because:

Also you are heating externally - those devices you mention use an element in the pot, therefore they are more efficient because they are just heating the water.

Mysobry, you need to recognize the significance of the difference between immersed heating elements and external heating elements. The Braumeister has a 2000W immersed coil, so its transferring ~90% of its energy right to the liquid. So the wort sees about 1800W, and people have said they need insulation to keep a rolling boil in those. External elements, just like an electric stove, are very inefficient because a lot of the heat is just lost to the air and the rest is transferred to the pot, then some of that finally transfers to the wort. They are 33-50% efficient typically. Your 1500W is maybe getting 750W to the wort. You can maybe boil 8 liters.

Play with Tim's spreadsheet. He did a nice job on that.

 

[LandoLincoln]

But enough of the number crunching. Plug the sucker in and let's see that boil!

 

[kal]

Yup. Math be damned!

I'd also be curious to hear how much these pads cost to do a typical ~6-8 gallon kettle as shown in the pictures.

Kal

 

[ryane]

Yup. Math be damned!

I'd also be curious to hear how much these pads cost to do a typical ~6-8 gallon kettle as shown in the pictures.

Kal

Over in the automation section Trimixidiver1 uses band heaters on his mashtun, looking on ebay you can get one relatively inexpensively to wrap around a keggle

https://www.homebrewtalk.com/f235/bucks-electric-brewery-479895/index4.html

you can see what he uses 1/2 way down the page

 

[mysobry]

Las Sunday I have performed as promised some tests with current configutation:

25L of water , silicone heater direct connected to power supply (220V AC) without any controller

Recirculating pump always on, digital temperature probe and a wattmeter on the main supply

Every 10 minutes I have a temperature sample as you can see in the picture

The rump up is quite good with more than 1C per minutes

After 1H 20’ the water start boiling and even if it is not a roll boiling like gas the evaporation was quite good.
The video shows you the result

http://youtu.be/_kmqVdywYiI

The power absorption was around 2200W

I can conclude that the technology is promising and adding a good thermal insulation can be used effectively for small volume and compact systems
Next steps adding the ArBir controller and complete insulation

Stay tuned

 

[Weezy]

That's 80% efficiency. That's quite remarkable for external elements. Manufacturers I've spoken to have never rated their stuff over 50%.

congrats! i'm glad it worked. Nice simple and clean setup.

 

[trboyden]

Not sure where you are coming up with your efficiency factor or what you are basing it on, but heating in general with electricity tends to be highly efficient compared to other heat sources. That is because it has a low energy content (3,412 BTU) per unit of measure (kilowatt) versus a fuel source such as propane which has 92,000 BTU per gallon. So while a high efficiency rating sounds good, it's not the whole picture.

It was a good test and I am glad the OP had success. But I look at it from the perspective of the typical home brewer:

• How easy is it to clean?
• How much does it cost?
• How long does it take versus other methods?
• How hard is it to put together/use versus other methods?
• Does it overcome any other environmental issues I have that prevent me from using another method?

I think if you step back from the novelty of this method; cleaning, cost, and time are big negatives. But for someone that has restrictions like apartment dwellers, this definitely has some promise versus not brewing at all.

That's 80% efficiency. That's quite remarkable for external elements. Manufacturers I've spoken to have never rated their stuff over 50%.

congrats! i'm glad it worked. Nice simple and clean setup.

 

[dyqik]

Eh? How does the size of the unit of measure affect the efficiency? That's just nonsense. Efficiency is heat energy into wort/energy used. Nothing more or less.

Even when calculating cost, the size of the unit doesn't matter, because units are divisible in both cases. The cost per unit is a factor, but not the size of the unit.

 

[ZackN]

Would the heat source coming from the sides change the physics of the boil?

I participated in a yeast experiment with a local brewery. They brewed, gave us a 5.5 gallon keg and a different white labs yeast. I think about 20 or 25 different ones total. They kept all these.
In the end there was left over wort, and a bunch of home brewers with empty carboys, they all got filled!:rockin:
^


Anyway... Their kettle was copper and steam fired. Aka, a copper pot, with a jacket around the outside where steam was pumped in to. We got to climb up and peek in the hatch, it boiled from the sides and not the bottom, it was pretty cool.

I think a side boil will be fine! also this is a pretty cool idea!