Designing a 2.5 gal rig

[Egas1949]

Hi all. I've been a theoretical brewer for a while as I haven't had the space or time to brew on my own, outside of Brew-on-premise shops. I'm currently cleaning the basement to set up a basic yeast lab and storage freezer after having successfully capturing some conan yeast and itching to capture more of my favorite beer yeasts. This will eventually turn into brewing and I'm committed to doing 2.5 gallon batches, it's the best fit for me. Anyway, in a lot of my theoretical designs I get focused on temperature control and for a while was dead set on using steam injection for rapid temp control. I'm ditching that and am shooting for something that has more temp stability. I'm thinking of a Mash tun-inside-an-HLT design. A large electric-cooler HLT fitted with a much smaller stainless steel hotel pan/bain marie pan; they come in rectangle and cylinder shapes. Then the idea would be to run it like a HERMS with the plumbing just going out the mash tun and up back in since it's all in the HLT like a hot water bath. I haven't worked out all the kinks but what do you think of the concept? It might be a heck of a lot of water to heat up at first but I imagine it will stay pretty stable once you get going.

 

[ChocolateMaltyBalls]

Hey I'm all for doing something different. Trying new things etc

Are you relying on the surface of the interior vessel for heat exchange or have some type of coil as well? That's gonna be a big HLT

 

[Egas1949]

If the mash tun being a stainless steel container is sitting in a hot bath, my assumption is that it would be the heat exchange I need, especially if the recirculation plumbing is in the bathwater by default. The only reason this would have a shot at working is because I'd be committed to 2.5 gallon batches and thus smaller volumes. If your mash tun is sitting in your HLT water, and you let your grains sit in the mash tun to equilibrate as the HLT comes to temp, everything is at temp when you pump in the water to start mashing. All I would need is plumbing coming out of the mash tun below the water line and coming up to pour back over the mash as the whole thing is sitting in a hot water bath. The questions now are; how big does that bath have to be? and how easily/fast can I raise the temp as I go?

 

[stlbeer]

al la sous vide brewing?

 

[chickens4life]

If you are going to go for surface area as your means of heat transfer (no herms coil), you are going to want to size the containers carefully so that you do not end up heat way to much sparge water just keep the mashtun in contact.

I think any benefits from that set up might be outweighed by the added work to clean it unless you are very careful about the design.

I have thought about doing the same thing, but haven't figured how to make it user friendly enough to make it worth doing. I am interested to see what you come up with.

 

[chickens4life]

okay so if you are using a separate boil kettle you could heat your water strike water there. that way the HLT only needs to hold sparge water. so for a 2.5 gallon batch i doubt you will spare with more than 2 gallons ever but lets say 3 to be on the safe side, then you have mashtun volume of maybe 5 gallons (again to be on the safe side in case you want to do big batches. that would make your outer container need to be about 8 gallons or there abouts. Unless you want to limit your max gravity you can brew, then you could go smaller.

 

[ChocolateMaltyBalls]

I don't think you will have any problems holding temps with this setup, but even with the small volume you have in mind I think the surface:volume ratio will be too low to change temps in a reasonable time. But hey I could be wrong, I'm just some guy on the internet.

 

[Egas1949]

Found this 14 qt cylindrical stainless steel container.

http://www.webstaurantstore.com/ava...steel-inset-for-s600-warmer/177S600INSET.html

If I got a large rectangular cooler with a heating element, something like this would be set inside it. Herms coil could would run into the bath in some configuration or another. I'll probably try to find a way to use a magnetic stirrer to agitate the water in the cooler too. I guess I'll have to design an array of inlets/outlets through the side of the cooler to mount the pump (or pumps). After hearing nightmare stories of stuck mashes and blown pumps I'm wondering if I should have a small grant or use a float switch on the mash tun to spare the pump.

 

[Egas1949]

OR maybe i'm overthinking the whole damn thing and I should do an eBIAB.

 

[doug293cz]

One potential problem with MLT inside the HLT is the buoyancy of the MLT if it is empty, or has a fill level much lower than the HLT. You have to design a solution that takes that into account.

Personally, I'd go with e-BIAB.

Brew on

 

[TheHopfather]

I think you're over complicating things. I'd vote for eBIAB personally.

 

[Peruvian802]

I suggest going simple at this stage and just get started. After you have a few brews under your belt you can decide how deep you want to go into it and you will also have a better understanding of what level of control you want to have.

 

[Egas1949]

Thanks guys. I start going down a rabbit hole when I start thinking about this. Always helps to have some perspective. I like the coleman party stacker coolers and might go with a two-cooler configuration that gravity pours into a kettle on a an induction range. They have a 4.5 gal model, so one for HLT and a 2nd for mash tun with a bag instead of false bottome; arrange element, plumbing and pump accordingly and I should be in business. It'll be a HERMS BIAB I guess. I wont be lifting the bag at all, just using is as a liner in the cooler instead of a false bottom our manifold, I may drain from directly beneath the cooler as this will be on one of those heavy duty wire shelves.

 

[Egas1949]

Alright, I think I'm probably doing a more conventional 2.5 gal vertical HERMS. I saw the Kickstarter for the BrewBot and it looked like their vessels were essentially hotel/steam table pans. I liked the idea as they could be sourced pretty easily; come in stainless, aluminum, and high-heat plastics; have a variety of shapes; come in capacities of 3 gallons and greater. I have a potential parts list that keeps growing, here https://www.pinterest.com/egas1949/25-gal-rig-femtobrewer/

I welcome all suggestion/criticism