10 gallon batches on a stovetop?

Hey guys, so here is my situation. I want to step up to 10-12 gallon batches from my current 5-6 gallon setup, but have not been enjoying brewing outside with my bayou classic burner due to the extra hassel and time added to my brewday. So i experimented a bit and put my 15 gallon stockpot on the stove to see if I could use 2 burners to get these bigger batches boiling inside. So I did a test with just water and I got it to a very weak but bubbling boil which hovered right around 211, maaaybe touching 212 here and there. I also boiled off 2 gallons in one-hour from a 10-gallon boil, as opposed to the 1 gallon evaporated in my 5-6 gallon setup, even though they are on the same stove. SOOO my question is, does this sound right and acceptable to you guys? A weaker boil concerns me a little bit but if I am boiling off 2 gallons in an hour there must be at least a somewhat decent boil going, right? Also, is 2 gallons per hour an unheard of amount to be boiling off? The pot is much wider than tall which I am assuming could account for such a high boil-off rate. Let me know if you guys think this is an acceptable brew-setup considering the boil-strength and unusual evaporation rate. Here is a picture for educational purposes (the bucket is there to show the size of the stockpot).

 

How much extra hassle can using a burner outside really add to your brewing? I would be concern with the weak boil

 

In all honesty, I could probably figure out a way to make the whole brewing outside thing much easier for me but I would really rather find a way to double my batch size without having to change where I brew. This is mostly just for convenience since I am used to brewing in my kitchen. However, I am also concerned when chilling my batch down outside for the 30 or so minutes it takes with that the wide-open kettle exposed to much more random things flying around in the air than when inside my house. I guess I just feel much more sanitary doing everything inside.

 

So is the consensus that I should avoid this setup due to a weaker boil? Is a weak boil truly something to avoid? The thermometer touched 212 although just barely and there was obviously plenty of boil off (2 gallons) and it certainly had some bubbling going on just not as strong as my usual setup gets. If so then I guess I will look into moving my 10 gallon setup outside even though I really dont want to.

 

If you boiled off 2 gallons or close to 20%, I would guess your boil is adequate and would give it a try...you could also make a heatstick which would insure a healthy boil as well as cut some time off the brewday w/ faster heating times.

 

After boiling off 2 gallons I had the same feeling. Maybe I will just try out a relatively inexpensive batch to see how it works.

 

Looks like you have a "commercial" style range... I have a Wolf, and I'm able to boil 7 gallons with no issue (on a single burner). I'm doubtful that I could get a 10 gallon batch to boil vigorously in a reasonable amount of time, even if I could use two burners.

 

With the 2 burners going, it took me 30 minutes to get from about 130 degrees to 211-212 for a weak boil. I mean this thing was boiling just very weak, so does anyone have a conclusive thought on doing this or should I just experiment with a cheaper batch to see if it works? Or abandon this thought all together and suck it up and bring everything outside?

 

When I used to stovetop, sometimes I would cover about half, or a little more of the kettle top w/ a doubled piece of aluminum foil to keep a bit of heat...looks like your kettle has a large surface area and gives up a ton of heat out the top and this might help.

 

I just did a 8 gallon batch with 10 gallons of wort in a 12.5 gallon kettle. I was not sure that I could get a good boil but I indeed did. I boil off about 1 gallon an hour and all my batches have been very tasty. I say roll with it.

I like to taste proof of a rolling boil batch versus vigorous boil. IMHO prolly no difference.

 

This is sort of OT, but it may help if you want to keep on brewing inside...

I started with a turkey fryer and a bbq gas tank in my kitchen, in the middle of the winter. The CO2 alarm in the kitchen never went off (I didn't expect it to, we use all 5 burners on the stove quite often and it never when off with those either).

It did get pretty steamy in the kitchen though, nothing that cracking open a window did not resolve.

YMMV. Use common sense when playing with fires in the house =)

 

I may be wrong but if you are just barely getting to 212* with plain water then wont it be much harder to get to that temp when you have a ton of dissolved sugar? I feel like my wort doesn't boil until it is close to 220*.

 

Not nearly that much, H-ost. I did a rough calculation for my normal 10lb in 5 gallon batch, 1060 something.

10lb of grain is about 4.5kg. At 62% sugar, that’s 2.8 kg. Divided by 342g/mole, that’s 8.2 moles. Figure a 20L batch, that’s .4 moles/liter. At .51Cº/m that’s .2Cº, or a little less than .4Fº

If somebody has a better take on the chemistry, go for it. Just don’t make me remind you about significant figures.

Y’all have fun with those big batches, it’s all I can do to lift five gallons in a carboy.