Electric BIAB and Nylon Voile Experiment

Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum

Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

gunner65

Well-Known Member
Joined
Feb 3, 2010
Messages
843
Reaction score
22
Location
Lexington, KY
If you ever wondered if nylon voile will withstand touching the element during the boil it will.

My setup is a 5500W ULWD element. Last night I was cleaning my setup in prep for a brew day today. I have heard some people burning the bag on the element and I have heard others say they don't.

I took a scrap piece of the voile I had and tied it around the element snugly. Let the water come to a rolling boil for ten minutes then shut it down. Pulled the material out not a mark on it.

Now that stainless cage I built to keep the bag off the element seems like a waist of my time and efforts. I fretted over how to cover the element for some time before coming up with my design. I think it takes up too much space so I am glad that my experiment worked out.
 
Things may change when you put grain in the bag. I hear it will scorch the grain for sure. Don't give up on the cage, it's not a bad idea even if you're just keeping stress off the element so it won't leak.
 
As long as there's sufficient liquid to carry the heat away (as a BIAB mash should have), it shouldn't be a problem.

I've used a HWD heat stick to step-mash a 2 qt/lb mash before, so it's doable, with care.
 
I think ScubaSteve has a valid point. Even if the bag turns burn/melt, the grains that surround the element could scorch. Furthermore the element is suspended in your kettle and the weight of the grain *could* put stress on the element. So it's valid to at least think about these issues.

Concerning weight on the element, my solution is to add grain to the mash in small amounts. In addition to preventing dough balls, the grain 'wraps' around the element rather than having a lump sum get dropped on it.

Just items to consider...
 
I just do not see grain being scorched at mash temps. The element is barely even on to maintain 150-160F. As far as weight on the element..that could be a problem.
 
Well finally got around to trying the brew without "elemental protection" no problems at all. No scorching on the grain and the element was not stressed at all. Also not to toot my own horn but I got a 77.8 percent brew-house eff. I never even came close batch sparging I am loving the BIAB.
 
I know you said it wasn't needed after all, but I'd like to see the cage you came up with to protect the bag from the element.

I'm working on moving up to a full electric keggle system. My short term goal is to get an electric brew-in-a-bag system up and running with one vessel. Later, I'll add two more kegs (and a bunch of other stuff) to have a full HERMS. I have a Camco 5500W ULWD element on order, but hadn't quite figured out how I was going to mount it and what the configuration would be with respect to the rest of the keggle components. I'd love to see what others have done.
 
Things may change when you put grain in the bag. I hear it will scorch the grain for sure.

Steve is right. I demonstrated this last night with my CB20. I wanted to try BIAB. So first, I tried my best to burn the bag on the element with only water. I could not get it to burn/melt/weaken at with 100% power and a full boil.

Feeling confident, I mashed in at 130F, recirculated to 152F...and the pump started to clog. I limped it through the mash (stirring frequently). After removing the bag, I found a nice burnt hole in the bag where it contacted the element. About a cup of grain had escaped - most of it was recaptured by continuing to recirculate into a smaller bag.

There was a nasty smell of cigarette ash through the boil and at the end I found my element was coated in charcoal with several crispy grains wedged in the center of it. Tasted ok, but I can't get past that aroma (yeah, I pitched anyway).

The good news:
1. I no longer have to wonder about this question.
2. The CB20 performs BIAB recirculating step mashes nicely (130-152 in 15min, then 152 to mash out in 10 min).
3. The 5gal paint strainer type bag holds 8-9lbs of grain.
4. I got the same efficiency as I normally do (65%) from my coarse crush - expecting better with a finer crush.
5. 4.5 hours start to finish with a 90 minute boil.
6. I get a new kettle/steamer pot to retrofit my CB20 system for more BIAB shenanigans. https://www.pelicansky.com/productdetail.aspx?id=115&cat=72

Thanks to jkarp, ScuabSteve and others who inspired me to try electric brewing. It is fun even when you are destroying things.
 
Steve is right. I demonstrated this last night with my CB20. I wanted to try BIAB. So first, I tried my best to burn the bag on the element with only water. I could not get it to burn/melt/weaken at with 100% power and a full boil.

Feeling confident, I mashed in at 130F, recirculated to 152F...and the pump started to clog. I limped it through the mash (stirring frequently). After removing the bag, I found a nice burnt hole in the bag where it contacted the element. About a cup of grain had escaped - most of it was recaptured by continuing to recirculate into a smaller bag.

There was a nasty smell of cigarette ash through the boil and at the end I found my element was coated in charcoal with several crispy grains wedged in the center of it. Tasted ok, but I can't get past that aroma (yeah, I pitched anyway).

The good news:
1. I no longer have to wonder about this question.
2. The CB20 performs BIAB recirculating step mashes nicely (130-152 in 15min, then 152 to mash out in 10 min).
3. The 5gal paint strainer type bag holds 8-9lbs of grain.
4. I got the same efficiency as I normally do (65%) from my coarse crush - expecting better with a finer crush.
5. 4.5 hours start to finish with a 90 minute boil.
6. I get a new kettle/steamer pot to retrofit my CB20 system for more BIAB shenanigans. https://www.pelicansky.com/productdetail.aspx?id=115&cat=72

Thanks to jkarp, ScuabSteve and others who inspired me to try electric brewing. It is fun even when you are destroying things.


I dont know if it is just the quality of nylon in the strainer bags vs the voile material but I have got two beers under my belt since ditching the element protection both mashes were 150-152F with a mashout 30 minutes at 170F. No burning or scorching. No off flavors what so ever. YMMV

I will try and get some pics of the cage up tonight when I get home. :tank:
 
Thanks! I'd love to see some pics. I am pretty stoked about BIAB regardless. Went ahead and ordered a 2000W 120V low watt density element to further reduce the chances of repeating.
 
I cannot speak to the low watt density elements and burning of the bag. I have a ULWD. So the cage or a false bottom may be your best bet.

Now to remember the photo........
 
Here you go. Dont even ask where to source the material it was left over from an environmental chamber repair sitting in a parts bin in the back of our lab.

IMG_1033.jpg


IMG_1032.jpg
 
I just made my first AG BIAB batch last weekend. Used a home made voile bag, had about a 14lb grain bill, and didn't use any sort of cage over the ULWD 5500W element. No problems whatsoever. I may eventually fashion a cage just to be on the safe side and keep the weight off the element, but I will continue to confidently brew in the meantime without one.
 
I know I'm digging up an older thread here, and I've also documented this in my build thread here ,but I think this is relevant info to add to this post as well. I've been doing BIAB in a converted keg with a 5500w ULWD element. I've probably done 10 or so brews so far. Each time, I have done a full volume mash with approx. 9 gallons of water. I've also always had the bag rest directly on the element, even while raising the temp to mash out and have never had a problem.

Lately, I've been trying to troubleshoot a grainy taste in my light beers. Though I use RO water, add 1g of CaCl per gallon, and 2% acidulated malt to the grist, I believe that it's not enough to put the mash into the proper pH range since I'm doing full volume mashes. Before breaking down and spending 100 bucks on a pH meter, I wanted to try and do a mash using approx. 1.7q/lb and then just top off with the remainder of water.

I decided to do a Blonde and added 5 gallons of water for my mash. I double bag my mash. First I line the kettle with a fine voile bag, then inside of that is a pretty coarse mesh bag. After douging in, my mash temp dropped below what I set my PID to, so the element kicked on. Immediately I smelled something burning. I lifted the bag and immediately saw grain in my kettle. Uh oh! Well, after pulling the bags out and inspecting, here's what I found:

This was the outer voile bag:
DSC_0001.JPG


And here's the inner mesh bag:

DSC_0002.JPG


I've never had any issues doing full volume mashes with the bags directly resting against the kettle. I've also never had issues with hops sacks getting wedged in between the element and my immersion chiller during the last 15 minutes of the boil. Guess without as much water circulating around the element, it got much hotter than usual and burned through the bags.
 
Interesting find. I have done the bag on the element since last Feb no problem. I think I will stop telling people it is ok to do this.
 
Interesting find. I have done the bag on the element since last Feb no problem. I think I will stop telling people it is ok to do this.

Yeah, I've never had an issue either. Maybe because the mash was so thick, there wasn't enough water surrounding the element to carry away the heat. The element had quite a bit of char on it, but was able to successfully scrub it all off with a scrubby pad and some Barkeeper's Friend.

I just started doing a recirculated mash to help me keep constant temps, but after this I may have to just kill the element all together during the mash.
 
I am in the process of switching from the keggle to a bayou classic with crab basket so I wont have to worry anymore about that. Like my keggle but now that I am single vessel only I want to make my BIAB sessions that much easier. I had thoughts of expanding to three vessel but cannot seem to justify it the way my beers are tasting with BIAB.
 
I have a theory but need a way to test it. I do single vessel recirculating BIAB using a 60 qt bayou classic with crab basket lined with a voile bag. I have opened up the holes in the basket to aid in flow (the stock holes are too restrictive).

I brewed several batches with no problems and then suddenly had 2 in a row with that "ass-tray" taste and had to dump 'em. Discovered burnt black residue on my element (ULWD 5500 Camco). Here's where my theory comes in: Those two burned batches were also when I experimented with different recirc flow rates, to the point that I actually had the liquid level rise in my kettle because the pump was drawing from the bottom of the kettle faster than the wort could drain back through the grain bed and bag. I believe this may have caused cavitation/airspace around the element allowing it to essentially "dry fire" and scorch the wort.

I have since refined my method to cranking up the recirc and stirring like crazy during temp ramps and them reducing the recirc to a trickle once the temp has stabilized where I want it.

Any ideas on how to test this conclusively without sacrificing perfectly good wort or using a heat-proof under-water camera?
 
thughes,

Without getting into "stuff", I firmly believe your conclusion is absolutely spot on. I also believe a lot of people think that the ULWD elements won't "burn" the wort. That is not the case. The ULWD elements are designed so that they (in theory) will not burn out if they are dry fired. In fact, when dry fired, they will hit temperatures way over 350°F.

So in summary, with a severly restricted flow, scorching is primary on the list of ..ah.. "stuff happens".

P-J
 
Yeah, need to keep recirc rates slow. I had the same thing happen - I opened up the pump a little too much, and I both burnt a hole in my bag and popped an element (it was HD). I'm almost sure that the too-quick recirculation created an air pocket around the element.

Since then I've kept recirc rates slow and have had no problems. I also went back to single-crushing my grains at the LHBS. I double-crushed for a while, and got great efficiency (~78%), but I'm still a little spooked about having too much flour in the grist for the recirculating water to flow through smoothly enough. So for now I accept 63% efficiency, but am less worried about things going wrong.

Even though it's more of a PITA to fix, I still love my eBIAB!
 
Yeah, need to keep recirc rates slow. I had the same thing happen - I opened up the pump a little too much, and I both burnt a hole in my bag and popped an element (it was HD). I'm almost sure that the too-quick recirculation created an air pocket around the element.

Since then I've kept recirc rates slow and have had no problems. I also went back to single-crushing my grains at the LHBS. I double-crushed for a while, and got great efficiency (~78%), but I'm still a little spooked about having too much flour in the grist for the recirculating water to flow through smoothly enough. So for now I accept 63% efficiency, but am less worried about things going wrong.

Even though it's more of a PITA to fix, I still love my eBIAB!

And that's the kind of evidence I am looking for: "...popped an element".

I'm thinking that could not possibly happen unless the liquid were removed from the vicinity of the element long enough for the surface temp of the element (or a section of the element) to rise very rapidly as if it were dry-fired.
 
And that's the kind of evidence I am looking for: "...popped an element".

I'm thinking that could not possibly happen unless the liquid were removed from the vicinity of the element long enough for the surface temp of the element (or a section of the element) to rise very rapidly as if it were dry-fired.

yep, my thoughts too.
 
Very good info for me as I switch to a bayou classic with boil basket. Thanks guys for resurrecting this thread.
 
Here's another trick for optimizing your flow rate: I slipped a small o-ring over my sight tube so I can set it at the same level as the liquid. I open up the flow on the recirc pump until the level starts to drop in the sight tube (indicating that you are pulling it out faster than it can drain back through the bag) and then back off the flow slightly until the liquid level rises back up to the level of the o-ring.

I also mark the liquid level with the o-ring before starting the boil so that I can have a quick visual reference of my boil-off rate during/after the boil.

6366364497_778b345b4b.jpg
 
thughes said:
Here's another trick for optimizing your flow rate: I slipped a small o-ring over my sight tube so I can set it at the same level as the liquid. I open up the flow on the recirc pump until the level starts to drop in the sight tube (indicating that you are pulling it out faster than it can drain back through the bag) and then back off the flow slightly until the liquid level rises back up to the level of the o-ring.

I also mark the liquid level with the o-ring before starting the boil so that I can have a quick visual reference of my boil-off rate during/after the boil.

Nice idea. I'm gonna borrow that one.
 
Thughes what size punch did you use?

I used my 1 1/4 chassis punch. Figured I'd get some use out of it considering how much the damn thing cost. I simply used the existing holes in the basket as pilot holes and punched out every other one.
 
Just got to use my new bayou classic with steamer basket and over head pulley. Wow what an easy brew day.
 
Seems to me a grant would solve the cavitation problem and be more hands-off than the o-ring on the sight tube solution. On the other hand, that is considerably cheaper and easier to implement. Good ingenuity on that one!
 
Thanks Sardoman. I've actually refined the method to a much less hands-on approach: Once the mash reaches temp I simply shut the pump off, put the lid on, and come back in 90 minutes. 9-10 gallons of water and 12-15 lbs grain (on avg) is a lot of thermal mass and I don't worry too much about the 1-2 degree drop over the course of an hour-and-a-half. :D
 
Gunner, did you do the swiss-cheese mod or just use the basket with the stock holes?
 
thughes said:
Gunner, did you do the swiss-cheese mod or just use the basket with the stock holes?

I punched seven 1.25" holes in the bottom. I only recirculate with the valve half open.
 
Hey everyone, thanks for your comments. I am looking to make a ebiab 10gal setup in the future and like to hear how things work for other people. I brew 5 gal full boil split pot on my stove and since i dont have a pump, when i use one of those strainer baskets I find it makes it difficult to keep the temperature of the water consistent.

Since you are using 220v, could you not just install 2 switches for the two hots on the 220v cord and disable one of the hots making the power output 1/4 for keeping the mash temperature? Would this not prevent the bag from scorching?
 
Hey everyone, thanks for your comments. I am looking to make a ebiab 10gal setup in the future and like to hear how things work for other people. I brew 5 gal full boil split pot on my stove and since i dont have a pump, when i use one of those strainer baskets I find it makes it difficult to keep the temperature of the water consistent.

Since you are using 220v, could you not just install 2 switches for the two hots on the 220v cord and disable one of the hots making the power output 1/4 for keeping the mash temperature? Would this not prevent the bag from scorching?
With that type of set up you need to keep the mash fluid moving/recirculating. Otherwise you will only be adding heat to the area around the element and it cannot regulate the entire mash volume temperature.

(Unless I do not understand you planned set up.)
 
Back
Top