Electric Direct-Fired MLT

Just thinking "out loud" while I sit here planning my new system that I hope to start work on this spring. I will hopefully be able to move towards electric 15.5 gal keggles later this year and I am thinking about a "direct-fired" electric MLT.

I think the whole key to this concept would be to devise a simple way of elevating/raising the false bottom to height that would allow installation of an electric element below the FB (element would only contact the mash liquor and not the mash itself). Just a few thoughts...

1. I do realize that I would lose effective mashing capacity, but I brew 5.5 gallon batches 99% of the time so this isn't a big issue for me. Even losing 33% capacity would still leave 10gal for the mash which is plenty.

2. I would recirculate the mash liquor to maintain temps or step mash. The element and temp control would be maintained via PID as most people do.

3. The dip tube would still draw from the lowest point of the keggle, so dead space really shouldn't be an issue.

4. Direct fire in this manner would negate the need for a RIMS or HERMS setup (one less thing to worry about controlling)

I haven't totally thought this thru yet, so all thoughts are welcome. Just looking for others input so I can flesh out this concept and not miss something important.

That's a lot of space under the FB. Figure even if you put the element as low as possible in a flat bottom vessel, the FB is going to be at least 1.5" off the bottom. In a keg, the depression in the bottom holds a gallon. I'm guessing you'd end up with about 3 gallons under the FB so that amount would have to be added to your strike water. I think you'd be limited to no-sparge brewing.

So if I only lose 3 gallons, that leaves me with 12.5 gallons of mash capacity. For me this would be plenty for my typical 5.5 gallon batches.

Adding the additional sparge water to the HLT shouldn't be an issue. I fly sparge and see no reason why I would not be able to do the same with this set-up (using a typical sparge/return manifold on top of the mash). I really do understand the implications of lost capacity and "dead space". Why would I be limited to no-sparge?

Do you think the concept is valid considering I could avoid the use of RIMS / HERMS by directly heating and recirculating mash liquor?

I really don't have anything to add except that I find this topic interesting and wanted to bump it back up near the top!

Thanks.

MArio

Interesting question. How does having that large of a dead space impact your mashing grist ratio? Do you include the water sitting under the false bottom when determining the mash ratio? You are drawing from the bottom so the wort is not lost but I think you would have to run a pretty thin mash to cover your grains effectively...

why not just build a rims tube. I see no advantage to this since you would need to be recirculating.

I am with bobby that since you would have to use an extra 3 gallons of strike water you would have nothing left to sparge with

I considered this, drilled my MLT and installed the element, had a FB setup for it, and it was good to go. My element is mounted as low as physically possible but in the end, Bobby is right, there is 3 gallons of deadspace below the false bottom, and I was not comfortable doing that.

Definitely a valid idea though, and one I have not abandoned- I am just trying to find an alternative method to accomplish this. I have something up my sleeve, but I will reserve info until I have a chance to try it myself first.

Good luck.

I will say though, that fly sparging makes the idea more valid than my initial apprehension.

Say you go with 12lb of malt. In order to keep things fluid for good recirculation and lautering, you want a ratio of at least 1.5qt/gal above the FB. That's 4 gallons. Add 3 gallons for under the FB. Now your ratio is 2.33qt/lb.

If you drain the tun completely (like some fly spargers do) with no sparge, you'll get 5.5 gallons of runnings. That limits you to 1.5 gallons of sparge that will actually work towards getting sugar out. Any additional sparge water would just be in the tun to keep the bed fluid and ultimately won't be run off.

I was thinking of doing something similar with a Brew In A Bag setup. Electric heating element low in the kettle, some type of false bottom to keep the bag above the heating element, and eventually some type of recirculating system. It would be the poor man's version of http://www.speidels-braumeister.de/shop_content.php/coID/21/content/der-braumeister.html. Any thoughts?

jeffmeh, that was/is my inspiration as well. It can work, just the logistics to do it economically are in play right now in my case.

Thanks for the feedback guys. The thinner mash is definitely a good point that I failed to mention. Enzymes will be more diluted, but hopefully not to the point of losing out on conversion (and if so, maybe a longer mash will be in order). I've got nothing but time.

I think I'm going to at least attempt this setup once I get all my equipment together. If it doesn't work, I'll remove the FB and convert the tun to a boil kettle and look at RIMS as a back up option. I just like the idea of avoiding a RIMS or HERMS and using a direct fire method to keep additional pieces of equipment limited.

cyberbackpacker said:

jeffmeh, that was/is my inspiration as well. It can work, just the logistics to do it economically are in play right now in my case.

Click to expand...

I am proceeding on this step by step:

-My first brew was an extract kit in a 7.5 gal turkey fryer.
-I upgraded to a 15 gal aluminum kettle, and have done extract brews in that.
-I installed a weldless ball valve and have done extract brews with no-chill.
-I have acquired a metal cooling rack with legs, that will keep the BIAB off the kettle bottom, and a grill grate for the top that can be used for draining the bag. My wife and I (mostly my wife) constructed the bag this week (a ~56" diameter circle with a 1/2" nylon rope drawstring). I am planning my first all-grain brew in a bag session.

If I am happy with the BIAB process, my next steps may be:

-Construct a second bag, start with both in the kettle, remove the inner one after mashing, use the outer one as a hop stopper.
-Install an electric element in the kettle and ditch the turkey fryer burner.
-Install a PID to control the electric element (will I need this immediately for the electric element to be able to control the boil rate? I can certainly mash by bringing things up to mash temp, turning off the element, and insulating the kettle).
-Install a recirculation system that takes the water from below and outside the bag and returns it at the top and inside the bag
-Install a sight glass and thermometer for convenience.

If anyone sees any pitfalls or has any suggestions, I am all ears....

I picked up 4 kegs (three 15.5gal and one 50L) today (legally) for $20 a piece, so keggle construction will begin sometime in the next few weeks.

For now, 2 of the 15.5s will be my new HLT and BK. The other 15.5 will become a buddy's HLT and the 50L might become a BK for another friend just getting into the hobby (trying to decide if he'll actually stick with it for a while).

Once I find one more 15.5 keg at a good deal, I will proceed with the electric "direct-fired" MLT idea and report back (though it will probably be several months before I have all parts and wiring/circuits completed).

I was thinking about this recently as well. The one idea I had was to mount a heat stick above the false bottom, then surround it with a stainless steel mesh/bazooka screen sort of deal. I probably won't end up doing it, but it is at least feasible.

Bakins ghetto BIAB system uses a large strainer pot put puts in his BK . The strainer put has stand offs to allow for the element to clear underneath it. Once the mash is done he pulls the strainer out to let it drain for a bit and then is ready to boil with no transfer.

I have an idea to make the external RIMS HEX internal to the MLT. I got the idea looking at the merlin system.
There is a lot of heat shed through the HEX and plumbing, if you could minimize the surface area exposed to air (HEX/plumbing) then you can heat more efficiently. To solve the wasted heat from the HEX I propose one could mount the element from the bottom of the MLT vertically in the middle.
A tube large enough to contain the element would be welded and sealed to the bottom of the MLT protecting the grain. The tube would have to be long enough so that the grain bed will never be above it.
A donut shaped false bottom would be placed around the Hex tube. The mash would be drawn from the false bottom and then into the bottom of the hex tube, pushing the mash out of the top and back down into the grain bed.

Doing this will keep what used to be heat wasted from the hex directly in the MLT, external plumbing would be a minimum as well.

Some kind of float switch or level sensing switch would need to be mounted in the tube to keep the element from dry firing when the pump is not on or has lost it's prime. mounting the temp probe at the end of the Hex could pose a challenge as well.

If the element was big enough you could boil in the same vessel like the Merlin units do.

I'm thinking this is going to be my next big project once I get some fabricating gear. But, if some one wants to take a crack at it before hand they are more than welcome to it.

How come I am not understanding? I don't see how a element is going to take up 3 gallons of space. Would someone help me out on this? I understand the element wont sit on the bottom but, IIRC the last time I checked. About every 1" of height of a 15.5 gallon sanke equals about 1 gallon. With the depression the first 2" of height involves the skirt and that only equals 1 gallon of liquid. I am missing something I guess? I can see 2 gallons.


I also run a false bottom in a converted sanke and run 1qt/lb above the false bottom and have never had any issue with a un-fluid grain bed. I also run a pump on the mash tun purely for vorlauf. The pump is not used in any other operation.

GM, the center of the element hole is about 1.5" above the 2" depression height, this is needed to leave enough room on the vertical keg wall and clear the first depression ring to allow the jam nut to sit flush and not on the contour of the depression. I mounted mine as low as possible and the element is barely submerged right at the 3.5 gallon mark.

CodeRage, Thank you for the visual. I don't know why but I just couldn't imagine that shot in my head last night.

I'm thinking about something similar. See my thread, https://www.homebrewtalk.com/f11/single-vessel-all-electric-ns-nc-brewery-158608/

Here's another idea: use a hot tub/spa heating element. the style I have in mind has looks like this one - http://www.spaguts.com/Product.aspx?ID=2 - and mounts on the bottom of the keg via two 9/16" or so holes. The profile is very low.

I am building my eHLT with one of these. One drawback may be the wattage is high, though maybe you can get a lower wattage one to minimize caramelization of the wort. I just measured the profile of the one I am working on, and from the low point of the keg bottom to the top of the element is 2".

Just a few updates as I've been able to sell some old equipment and start picking up stuff for my new build. I still plan on the direct-fired electric mash. My new system will be a 5 gallon (with the option for 10 gallon) all keggle, all electric, two-tier system (with one pump). Everything will work off a 50amp GFCI breaker, with PID control on the BK and mash tun. HLT will run off a simple on/off switch. Only two vessels will ever run at the same time making it well within safe limits for 50amp service. I should never draw more than about 40 amps at any given time.

Today I either ordered (or won on eBay)
1 x 50amp GFCI Spa breaker = $39 shipped (got really lucky with this one on eBay)
2 x 25amp SSR + heatsink = $13.99 each w/ free shipping
2 x 240V 4500W LDW Camco = $8.40 each (for BK & HLT)
1 x 240V 3500W LDW Camco = $8.70 (MLT)
1 x PID Auber SYL-2352 = $44.50 (only ordered one for now to control BK)
1 x RTD Auber = $32.55

I'll start posting some pics when I get to cuttin' kegs. It'll be about 3-4 more months before I have ammassed all the components I want and need. The new mash tun will be the last vessel assembled. I'll just use my cooler until I can sell it.

Thought I would point you guys to some ideas I have thrown around today... really a potentially great breakthrough for electric direct fired MLT's

The big development thread:

https://www.homebrewtalk.com/f16/custom-mash-tun-161223/

And a few more ideas related to it that I posted about in scubasteve's thread trying for, essentially, a speidel's braumeister setup (relevant posts to above thread starts at #86):

https://www.homebrewtalk.com/f11/single-vessel-all-electric-ns-nc-brewery-158608/index9.html#post1862102

Hey Packer,
Thanks for the links. Definitely some interesting ideas on both. I just love the original ideas and builds that spring from them.

And for my project, I just got my first goodies in today.
https://cdn.homebrewtalk.com/gallery/showphoto.php?photo=33225&cat=846

And these just showed up too (despite the snow, sleet, and freezing rain here in NC)
https://cdn.homebrewtalk.com/gallery/showphoto.php?photo=33227&cat=846

Brian,

No prob... glad to share. There are some developments taking place where I hope to be able to start doing some beta testing and get some real world data. I will keep you informed.

For your elements, what part numbers are you using?

Good luck!

2 x 240V 4500W LDW = Camco 02583 (HLT and BK)
1 x 240V 3500W LDW = Camco 02523 (MLT)

I bought all three on line at,
http://www.hardwareworld.com/
The Camco web site has the best info for their own elements, they just don't sell direct.