Insulation of the kettle?

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turbo

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Hello,
I have a 15 gallon pot (70 litres) an plan to brew 5 and 10 gallon batches.
I will recirculate the wort and have heating elements below the false bottom under the bag, temperature probe will be at the top of the kettle (in the lid inlet)
Is there normally a need for insulation of the kettle when recirculating mashing or can I trust the temp probe, PID and elements?


Thanks in advance
 

RM-MN

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My experience with BIAB is that none of what you mention is necessary. Mill the grains very fine because you can with BIAB, heat the water to strike temp, stir in the grains, and by the time your temperature drops enough to measure conversion will be done.

If you intend to recirculate, then you need to have coarser grain particles because the very fine particles will clog the pores of the bag. That slows conversion. To keep the temperature constant during that longer mash you need to add heat during the mash. To keep the bag from burning you need to keep it away form the burner in your pot so now you also need the false bottom. To keep the temperature near the same throughout the mash, you need to recirculate. You have neatly boxed yourself in.
 

doug293cz

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If you do go forward with your plan to heat and recirculate during the mash, you want your temp probe that controls your PID to be close to the heating element, preferably in the recirc flow pattern. If the probe is remote from the element, you get both heat loss in the wort before it gets to the probe, and you have a time delay before you detect any overheating near the element. This can cause enzyme denaturing, or even scorching, of the overheated wort.

You can add a second temp probe to monitor the temp of the return wort, grain mass, etc. if you wish, but the controlling probe needs to be where the hottest wort will be.

Brew on :mug:
 
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turbo

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Hello and thanks for input.
I was thinking that re-circulation would improve the clarity (not a native english speaking person so perhaps wording issue here) of the wort and also allow me to have heat steps in the process.
The bag I purchased is a 400 micron, what should be a reasonable setting of the mill you think?
today I have it to 3/64".
I have a false bottom to clear the bag from the elements and so I hope I will not fry it, also I can regulate the effect on the element to avoid scorching the wort.
The temp probe I have today is in the lid just above the nozzle but I can just move it to the kettle outlet and then it
is closer to the heat elements - I however thought that it should measure on the top so any heat losses in the circulation are countered for and control the PID som that I know temp in the wort inlet rather than outlet, perhaps that is not a good thought process.. but in process industry this I understand is the standard approach.
If I find that the heating scorches I plan to use the counterflow chiller and a second HLT for HERMS but for simplicity I just wanted to use the boilers elements for a RIMS approach..
Not sure I understand how I have boxed myself in (and not sure what the expression means) - I think that recirculating BIAB and be able to heat gives good mash control with a minimal hardware impact. As said I was even thinking about circulating via the counter-flow chiller so I don't need to reconnect any hoses during the process.
 

BrewZer

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"Box yourself in" is to set up circumstances that force you to do things a certain way... in this case, your desire to recirculate (a step unnecessary in BIAB).

Without recirculating, you can grind smaller and not worry about clogging your bag's pores or your recirculating pump, and you won't need to add heat and won't have to worry about a false bottom, scorching your bag or the grains near the bottom/element. Smaller grind will aid in conversion, likely boosting efficiency above what you would otherwise expect. And if you heat a few degrees above your mash temperature, add the grains, stir them in so there's no lumps, and then insulate your kettle, your water will settle at mash temperature long enough to convert.
 
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turbo

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Thanks -
I get your point, but still I have all those opportunities as well if I like to go this path?
Perhaps the 400 micron bag is too of a wide mesh for real fine crushing so that perhaps was a useless purchase with your approach - again I have only a cheap monstermill so I dont expect so much from crushing/milling.

Also I read from your good post that having different temp sections is not worth while?
" (a step unnecessary in BIAB) "
I thought that it was important for the different enzymes but I might be completely wrong - why are the automation guys with Grainfaters and such spending time with this steps if unnecessary?

Again thanks for educating posts, I am learning from youtube and fellows so I do go wrong here and there :|
I really appreciate your time answering questions and I hope our community can benefit from your posts and not only I.
 

isomerization

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My experience with BIAB is that none of what you mention is necessary. Mill the grains very fine because you can with BIAB, heat the water to strike temp, stir in the grains, and by the time your temperature drops enough to measure conversion will be done.

If you intend to recirculate, then you need to have coarser grain particles because the very fine particles will clog the pores of the bag. That slows conversion. To keep the temperature constant during that longer mash you need to add heat during the mash. To keep the bag from burning you need to keep it away form the burner in your pot so now you also need the false bottom. To keep the temperature near the same throughout the mash, you need to recirculate. You have neatly boxed yourself in.
I agree with this philosophy for single infusion mashing. How about if you are doing step mashes? Do you think recirculating while raising the temp is important?
 

Barbarossa

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I don't do biab so i can't tell. But I have an Anvil with a grain pipe and when doing step mashes I always recirculate during then temp rise because I had trouble with stuff settling down on the element and scorching the hell out of it. I also don't recirculate in the pipe but outside of it so that I can recirculate at max flow without compacting the grain bed.
 

Bobby_M

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BIAB can be successful static or recirculated. Recirculated generally works better for people who want to step away for most of the mash, or if you have a programmed step mash. In a static system, adding heat generally requires stirring to distribute the heat.
 

Monmouth00

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While everyone's system is different, I have found that recirculating and step mashing has increased my efficiency.
 

BrewZer

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BIAB can be successful static or recirculated. Recirculated generally works better for people who want to step away for most of the mash, or if you have a programmed step mash. In a static system, adding heat generally requires stirring to distribute the heat.
Frankly, if I had a pump and two hoses pushing my mash water around in my kettle, I'd be too scared to walk away from it for longer than it takes me to drain my bladder.
 

RufusBrewer

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Frankly, if I had a pump and two hoses pushing my mash water around in my kettle, I'd be too scared to walk away from it for longer than it takes me to drain my bladder.
Turn off the pump, turn off the heating element, drain your bladder, return, turn on pump, turn on heating element.

I think with any BIAB method, you are better off insulating the kettle. Reduces some variables. Lets you tune into your system better. Example. With an insulated kettle a brew session in the summer and a brew session in the winter will tend perform closer to identical and predictable. Really comes down how much trouble and expense you want invest in adding insulation.
 
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