Author Topic: False bottom issue  (Read 1454 times)

Offline young_brewer

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False bottom issue
« on: January 06, 2011, 05:45:53 AM »
Hello Friends,
I'm using AG brewing system where my mash tun is a 50L sankey keg i got a false bottom screen made locally, but the problem is that there is 5L water underneath my false bottom now when i mash-in that 5L doesn't come in contact with my grains at all untill vorlauff so does this mean that my L:G ratio should be accounted for the 5L that doesn't come in contact with my grist? or shall I start recirculating my wort at a regular interval say every 15mins from the time i mash-in for the entire mash lenght???

Offline beerocd

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Re: False bottom issue
« Reply #1 on: January 06, 2011, 06:04:48 AM »
You sure about that? That's 1.3 gallons!
What is your False bottom like? Mine is just a round, flat, piece of perf.
I can't imagine more than a couple cups of liquid under that.

You can add a pump to constantly recirculate, or get another false bottom that sits flat on the bottom of the keg.
I'm pretty sure you would quickly tire of your manual recirculation idea.
The moral majority, is neither.

Offline hopfenundmalz

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Re: False bottom issue
« Reply #2 on: January 06, 2011, 06:50:38 AM »
I have a pico-system that I bought many years back.  It sits above the valve and pick up tube on a metal grid.  It has at least 2 gallons below the false bottom.

I don't include that volume in the water to grain ratio.  I do include it in the water needed calculation.  Brew a few times with it and you will decide how to handle the calculations.

A link so that you can see what it looks like.  The screens on mine are copper.
http://www.homebrewing.org/Stainless-Steel-PICO-style-keg-kettle-false-bottom_p_1010.html

I do recirculate with a pump and stir when heating for a step mash.  The pump is used to vorlauf.  You need to throttle the pump's output at vorlauf, or you can suck the mash down causing it to stick, or even worse you can collapse the false bottom.  The suction on from the pump applied to the large area of the false bottom results in a large force.
« Last Edit: January 06, 2011, 06:55:00 AM by hopfenundmalz »
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Offline beerocd

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Re: False bottom issue
« Reply #3 on: January 06, 2011, 07:04:45 AM »
I do recirculate with a pump and stir when heating for a step mash.  The pump is used to vorlauf.  You need to throttle the pump's output at vorlauf, or you can suck the mash down causing it to stick, or even worse you can collapse the false bottom.  The suction on from the pump applied to the large area of the false bottom results in a large force.

Ah, directly heated mash tun! I get it now. In order to not scorch the grain.
I'm so used to reading about people with their keggles setup as RIMS systems. Never though about Direct fired.
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Offline johnf

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Re: False bottom issue
« Reply #4 on: January 06, 2011, 08:20:40 AM »
Mine has a gallon or so I guess, it is a Sabco false bottom.

I don't consider water to grain ratio, I want a certain amount of water above the grain.

I've found mash performance to be pretty insensitive to water/grain ratio within the range of commonly used ratios.

Offline tschmidlin

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Re: False bottom issue
« Reply #5 on: January 06, 2011, 02:23:12 PM »
I have a keggle with  about 1.7 gallons under the false bottom, and I don't include it in my mash thickness calculations.  If I always made 10 gallons it probably wouldn't matter, but if I make 5 gallons of something low gravity and did include that in the calculation then the grain doesn't get very wet.
Tom Schmidlin