Sparge over flow

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Weatherman

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Evening all

Just a quick question about how people set their AIO system for sparge.

Do you start you re circulation pump running at full power and subsequently water is always going down the overflow pipe or, do you slow the pump down to limit the amounts of wart/water sat on top of the grain bed?

By not running the pulp at full power, more of the water stays in the kettle and remains at a good temp, tather than sat on to of the grain cooling….but that is pretty tenuous.
 
I’m guessing the OP means during the mash rather than the sparge, because it’s generally not possible to recirculate whilst sparging in most AIOs because the malt pipe is up in the air!

That being the case, I try and balance the recirculation to avoid the wort flowing down the overflow, simply to get an idea of how fast the wort is flowing through the grain bed. If it’s running at full bore and pouring down the overflow, it’d be hard to know if I have a slow or stuck mash.
 
Apologies, you are correct, I can’t fathom why I said sparge rather than mash.

But yes, when mashing, do you restrict the flow or set the overflow to function and run the pump at full bore.

If you delete the overflow, don’t you run the risk of there being no water under the basket if the mash is slow?
 
I have struggled in the past with my AIO (Brewzilla Gen 4) but I saw some advice on here a few weeks ago about leaving the mash for 10 minutes before starting the pump. I tried that on my last brew and it definitely helped but I can't remember if I had my pump running at full speed, I also throw a few handfuls of rice hills into the grain before mashing in
 
I have struggled in the past with my AIO (Brewzilla Gen 4) but I saw some advice on here a few weeks ago about leaving the mash for 10 minutes before starting the pump. I tried that on my last brew and it definitely helped but I can't remember if I had my pump running at full speed, I also throw a few handfuls of rice hills into the grain before mashing in
To me, that makes sense. It gives the grains etc time to absorb and swell so when you do start putting water over the top it’s more likely to pass through.

The brew I did yesterday had 200 g of husks in (purchase as a kit from MM) but it was a very slow mash. I usually use rice hulls and this does seem to make a difference.

It was a hazy NEIPA using Idaho 7. No hop additions at all until flame out. Be interesting to see how it turns out. Hit the 1.047 OG spot on though.
 
I restrict the recirculation so that it doesn't go down the overflow. Wort going down the overflow doesn't add anything useful (it just prevents the pump running dry) so I treat it like a pressure relief valve. It's a safely measure rather than something I intend to use.

If wort goes down the overflow it can also take extra floaty bits of grain with it.

I start the recirc at the start of the mash on about half speed, then give it a good stir after 5 and 10 minutes. After this I can have it on full speed and nothing goes down the overflow (G30)
 
I restrict the recirculation so that it doesn't go down the overflow. Wort going down the overflow doesn't add anything useful (it just prevents the pump running dry) so I treat it like a pressure relief valve. It's a safely measure rather than something I intend to use.

If wort goes down the overflow it can also take extra floaty bits of grain with it.

I start the recirc at the start of the mash on about half speed, then give it a good stir after 5 and 10 minutes. After this I can have it on full speed and nothing goes down the overflow (G30)
Good advice, here!
The Grain bits can be stopped by using a tea strainer over the central overflow pipe.
If you dough in / mash in slowly and thoroughly (it takes about 20 mins minimum) and use some rice hulls for either wheat / rye grain bills or very large grain bills, there should be no issues with running a G30 GF at full throttle on the pump. Stirring the mash half way through enhances your efficiencies, but be careful not to touch the "grain bed" at the bottom of the mash pipe, as this always gets you into stuck sparge land.
 

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