Recirc, Wilser Bag, Crush Size

[Horsepuncher]

I’m recirculating using a Wilser bag and getting a stuck mash. I’m milling my grains down to about 32 mil. For those using a similar process, what size are you milling your grains to?

 

[IslandLizard]

I highly doubt BIAB is meant for recirculation mashes, there's not enough flow and chances are the drain gets plugged up with the bag. You'd need at least a false bottom and an exit port that can drain from underneath it.

 

[LittleRiver]

Why do you want to re-circulate?

If you haven't already, try brewing with just the bag, no re-circulation. You'll make excellent beer with far fewer hassles.

 

[hottpeper13]

WTF is 32 mill? for recirc you will need a 1/4" mesh false bottom from Brew Hardware and a .035-.045 crush, that's thousands measured with a feeler gauge. I've been there and am with LittleRiver. (like the band too) See no need to recirc, even the "way expensive" herms systems you can get can only HOLD mash temps, so just insulate the piss out of it and make great beer!

 

[odie]

recirc has been iffy on my set up so far. I use a steamer basket to support my bag since I have a heating element inside the kettle and a probe thermometer (that I apparently didn't really need but it fits thru the sight tube fitting really nice).

even with all the steamer basket holes exposed (removed the basket sidewall liner) the flow is very slow thru the bag with the typical BIAB tight crush. It does flow, just slower than my teeny tiny pump.

To recirc with a bag you must have enough of the bag material exposed (meaning not touching the kettle or any other solid object/surface) to allow the mash to flow thru the material. A false bottom of some type to hold the material away from the kettle bottom and/or sides to allow maximum bag exposure & flow.

My standard "steamer basket" has holes all over it but not enough holes. the total surface area of the bag that is thus exposed is not sufficient to maintain flow so I currently have to cycle the pump and stir occasionally.

I'm still experimenting with variations to achieve consistent BIAB recirc.

But as noted above...recirc is not needed either. If your kettle is bare inside with no internal element, recirc is simply not needed since you effectively have no voids to worry about. No wort not in the mash. If mine was still propane fired I would have nothing inside and just a bag too.

 

[Horsepuncher]

.

 

[Horsepuncher]

I highly doubt BIAB is meant for recirculation mashes, there's not enough flow and chances are the drain gets plugged up with the bag. You'd need at least a false bottom and an exit port that can drain from underneath it.

Yes. I have a brew hardware false bottom and exit port. I’m looking for info from people with experience.

 

[Horsepuncher]

WTF is 32 mill? for recirc you will need a 1/4" mesh false bottom from Brew Hardware and a .035-.045 crush, that's thousands measured with a feeler gauge. I've been there and am with LittleRiver. (like the band too) See no need to recirc, even the "way expensive" herms systems you can get can only HOLD mash temps, so just insulate the piss out of it and make great beer!

A mil is a measurement that equals one-thousandth of an inch, or 0.001 inch. 32 mil is the same as .032". I know many people say that you don't need to recirc, but I want to. Thanks for the info on the 35 - 45 mil.

 

[Horsepuncher]

Why do you want to re-circulate?

If you haven't already, try brewing with just the bag, no re-circulation. You'll make excellent beer with far fewer hassles.

I have, many time. I'm using a pump for a counterflow chiller anyway. I'm also now using it to recirc my mash, the way plenty of other people do. Just looking for info from people that brew in a similar way.

 

[odie]

OK then...how much exposed surface area does your current set up have? The recirculation is only going to happen where wort can flow thru the bag into the open area around your exit port. With a tight BIAB crush, the flow rater per square inch of exposed bag is very low. Thus you need to maximize the exposed bag surface. Simple as that.

So look at your false bottom to start with...how many square inches of material touching the bag and how many square inches of bag exposed? Is that false bottom a domed metal plate with a bunch of small holes or is at an open grid like a "cake cooling rack"?

 

[odie]

A picture is worth a thousand words. U can plainly see the issue. There is more basket than holes for wort to flow. I removed the side liner to expose the side holes and my recirc improves but still cannot keep of with the pump. Also your pump size is a big factor. Smaller output the better. It’s not a race. It’s a 1-2 hour mash.

 

[Horsepuncher]

recirc has been iffy on my set up so far. I use a steamer basket to support my bag since I have a heating element inside the kettle and a probe thermometer (that I apparently didn't really need but it fits thru the sight tube fitting really nice).

even with all the steamer basket holes exposed (removed the basket sidewall liner) the flow is very slow thru the bag with the typical BIAB tight crush. It does flow, just slower than my teeny tiny pump.

To recirc with a bag you must have enough of the bag material exposed (meaning not touching the kettle or any other solid object/surface) to allow the mash to flow thru the material. A false bottom of some type to hold the material away from the kettle bottom and/or sides to allow maximum bag exposure & flow.

My standard "steamer basket" has holes all over it but not enough holes. the total surface area of the bag that is thus exposed is not sufficient to maintain flow so I currently have to cycle the pump and stir occasionally.

I'm still experimenting with variations to achieve consistent BIAB recirc.

But as noted above...recirc is not needed either. If your kettle is bare inside with no internal element, recirc is simply not needed since you effectively have no voids to worry about. No wort not in the mash. If mine was still propane fired I would have nothing inside and just a bag too.

OK then...how much exposed surface area does your current set up have? The recirculation is only going to happen where wort can flow thru the bag into the open area around your exit port. With a tight BIAB crush, the flow rater per square inch of exposed bag is very low. Thus you need to maximize the exposed bag surface. Simple as that.

So look at your false bottom to start with...how many square inches of material touching the bag and how many square inches of bag exposed? Is that false bottom a domed metal plate with a bunch of small holes or is at an open grid like a "cake cooling rack"?

https://www.brewhardware.com/product_p/biabbottom15.htm

I have plenty of exposed bag. It's either a standard BIAB Bag is too fine to recirc, or I need to increase the size of my crush.

I do lots of Belgian beers so was excited with the idea of trying some step mashes which is why I want to recirculate. (I know, I know, modern grains are already modified and there's not reason to do a step mash, the same as there's no reason to recirculate)

 

[odie]

Behold the power of my mighty mash pump. It easily out runs the mash flow.

 

[odie]

That's a perfect false bottom for your needs...Show me your pump...I bet it will reveal your problem...

 

[Oginme]

I recirculate using a Wilser bag and a brew bag in my Anvil Foundry. There are a few things to be careful of if you do a recirculation for any mash. The first is to allow the grain bed to settle a bit before starting any recirculation and the second is to start with a very low flow level and slowly increase it to a modest flow. My recirculation stream is a bit less than the thickness of a pencil for reference.

You want to avoid a high downward pull to prevent compacting the mash and a heavy flow from above which can cause channeling through the grain bed. You want to keep the grain bid "floating" as much as possible to allow for good liquid exchange around the grain particles.

 

[Horsepuncher]

That's a perfect false bottom for your needs...Show me your pump...I bet it will reveal your problem...

I don’t have a picture but it’s a Chugger Pump.

 

[Horsepuncher]

I recirculate using a Wilser bag and a brew bag in my Anvil Foundry. There are a few things to be careful of if you do a recirculation for any mash. The first is to allow the grain bed to settle a bit before starting any recirculation and the second is to start with a very low flow level and slowly increase it to a modest flow. My recirculation stream is a bit less than the thickness of a pencil for reference.

You want to avoid a high downward pull to prevent compacting the mash and a heavy flow from above which can cause channeling through the grain bed. You want to keep the grain bid "floating" as much as possible to allow for good liquid exchange around the grain particles.

Thank you! Do you mill your own grains? If so, do you know your crush size? On my last batch, which had a larger grain bill than my typical, my flow seemed to be very restricted. I’m wondering if the bag weave is slowing it down or my grain crush.

 

[ScrewyBrewer]

A mil is a measurement that equals one-thousandth of an inch, or 0.001 inch. 32 mil is the same as .032". I know many people say that you don't need to recirc, but I want to. Thanks for the info on the 35 - 45 mil.

I recirculate using a Wilser bag and a .032 grain crush with no issue. In my 15.5 gallon kettle a typical BIAB grain bill has 23 pounds of grain and 12 gallons of strike water in the mash. You will want to give the mash a good stir four times an hour though, hope this helps you.

 

[Oginme]

I do weigh out and crush my own grains. I use a corona style mill, so the gap size is not a set measurement. I attached a picture of my typical crush. Even some of the more 'intact' kernels are fractured on the inside and fall apar twith a simple squeeze of thumb and forefinger.

 

[Jtvann]

I’m recirculating using a Wilser bag and getting a stuck mash. I’m milling my grains down to about 32 mil. For those using a similar process, what size are you milling your grains to?

Im glad you posted this. I just bought the exact same false bottom and a wilser bag. I was going to readjust my mill gap down from .040 to .035, but that's just a guess as to what the system can handle.

I've got a ssbrewtech recirculation manifold that I'd planned to set inside and on top of the grain bed. I'm only planning to recirculate enough to maintain temps. I got the 5.5 inch false bottom to raise above the thermo probe. I plan on brewing mid to late January, so if you get a setting that works, let me know. Obviously, use rice hulls.

 

[Horsepuncher]

Im glad you posted this. I just bought the exact same false bottom and a wilser bag. I was going to readjust my mill gap down from .040 to .035, but that's just a guess as to what the system can handle.

I've got a ssbrewtech recirculation manifold that I'd planned to set inside and on top of the grain bed. I'm only planning to recirculate enough to maintain temps. I got the 5.5 inch false bottom to raise above the thermo probe. I plan on brewing mid to late January, so if you get a setting that works, let me know. Obviously, use rice hulls.

I’m on a Blichmann with a boil coil. I just adjusted my milk to .035. We’ll see how that goes. I actually haven’t been using rice hulls. Perhaps that the missing piece. Thanks!

 

[Jtvann]

I’m on a Blichmann with a boil coil. I just adjusted my milk to .035. We’ll see how that goes. I actually haven’t been using rice hulls. Perhaps that the missing piece. Thanks!

I learned quick that with any recirculation rice hulls are mandatory. Some will argue that they're only needed when using oats or flaked adjuncts, but I use a full lb in all my brews.

Last week I used a basket, so this might not be as applicable, but my grain bill was 32 lbs total with 8 lbs being flaked oats/wheat. I recirculated at a fairly high rate the whole time without issue. My system is a brew boss with a center cofi tube, not recirculating top to bottom, so it doesn't compact on high speeds.

Im moving to a bag because I learned with that high of a grain bill, the basket volume leaves too much wort outside the grain. My next run will be the same setup as yours with a top to bottom flow at a much lower flow rate.

 

[Cato1507]

I’m recirculating using a Wilser bag and getting a stuck mash. I’m milling my grains down to about 32 mil. For those using a similar process, what size are you milling your grains to?

Lol, I must be odd man out here but I recirc my BIAB.
I use a Brew Bag and no false bottom and so far haven't had a stuck sparge.

I mill to credit card thickness as my feeler gauge.

As far as I can tell my grain bed stays pretty fluid on full volume batches.

My batches are typically 3.5-4.5 gal and I started recirculating when I started using a controller to maintain a consistent temp and feel that's working pretty well for me.

My whirlpool return is located just above the Boil Coil and i pretty much run the ports wide open.

When i stir, at maybe 20 min intervals there's of course some grain at the bottom but not much.

Quite possibly that my batch size in my 10gal kettle is aided by being thin in full volume, but whatever I'm having great success with it.

 

[Horsepuncher]

I learned quick that with any recirculation rice hulls are mandatory. Some will argue that they're only needed when using oats or flaked adjuncts, but I use a full lb in all my brews.

Last week I used a basket, so this might not be as applicable, but my grain bill was 32 lbs total with 8 lbs being flaked oats/wheat. I recirculated at a fairly high rate the whole time without issue. My system is a brew boss with a center cofi tube, not recirculating top to bottom, so it doesn't compact on high speeds.

Im moving to a bag because I learned with that high of a grain bill, the basket volume leaves too much wort outside the grain. My next run will be the same setup as yours with a top to bottom flow at a much lower flow rate.

I’m only using a 10g kettle in which I max out with about 11-12lbs of grain. Not ideal. Here’s my set up. Im using a hangover to hold the temp sensor and the recirc arm.

 

[Horsepuncher]

Lol, I must be odd man out here but I recirc my BIAB.
I use a Brew Bag and no false bottom and so far haven't had a stuck sparge.

I mill to credit card thickness as my feeler gauge.

As far as I can tell my grain bed stays pretty fluid on full volume batches.

My batches are typically 3.5-4.5 gal and I started recirculating when I started using a controller to maintain a consistent temp and feel that's working pretty well for me.

My whirlpool return is located just above the Boil Coil and i pretty much run the ports wide open.

When i stir, at maybe 20 min intervals there's of course some grain at the bottom but not much.

Quite possibly that my batch size in my 10gal kettle is aided by being thin in full volume, but whatever I'm having great success with it.

No issues with the bag scorching in your set up?

 

[Cato1507]

No issues with the bag scorching in your set up?

Nope. The ULWD Boil Coil I run mash at 90-95% power and no scorch whatsoever on my Brew Bag, and the bag is all over in contact with it.

I'm not the only one on the forum that does this using the Boil Coil and the others report no issues either.

I think the ULWD element and its design, allows it to work.

 

[Cato1507]

I’m only using a 10g kettle in which I max out with about 11-12lbs of grain. Not ideal. Here’s my set up. Im using a hangover to hold the temp sensor and the recirc arm.

Mine with Riptide pump and brew Comnander.

 

[Jtvann]

Couple things that come to mind when looking at your setups.

Cato, you're only recirculating the bottom portion of your mash. I'd really worry that if your temp probe is near the bottom that you dont have consistant temps throughout the whole mash. Heat rises, so maybe I'm worrying about nothing, but it does have me thinking. It is good that you're able to leave the lid on as that will retain heat.

Horsepuncher, leaving the lid off due to your mounting apparatus contributes to a ton of heat loss. I'd also worry about channeling with using a
Loc-line. All the wort flow is going back into that one spot. I'd try to make sure that your wort flow is just a bare trickle and there's a good inch or two of water above your grain bed.

 

[LittleRiver]

...don't need to recirc, but I want to....

That's all the reason you need. Homebrewing is a hobby, you get to enjoy it however you like!

 

[Cato1507]

Couple things that come to mind when looking at your setups.

Cato, you're only recirculating the bottom portion of your mash. I'd really worry that if your temp probe is near the bottom that you dont have consistant temps throughout the whole mash. Heat rises, so maybe I'm worrying about nothing, but it does have me thinking. It is good that you're able to leave the lid on as that will retain heat.

Horsepuncher, leaving the lid off due to your mounting apparatus contributes to a ton of heat loss. I'd also worry about channeling with using a
Loc-line. All the wort flow is going back into that one spot. I'd try to make sure that your wort flow is just a bare trickle and there's a good inch or two of water above your grain bed.

Thanks, actually it's working better than expected with pump wide open, and when I stir i only get a 2 degree difference, which is acceptable to me.

My probe is located at mid point of my mash, and while nothing is ever ideal, for a simple system and brewer it works.

 

[odie]

Couple things that come to mind when looking at your setups.

Cato, you're only recirculating the bottom portion of your mash. I'd really worry that if your temp probe is near the bottom that you dont have consistant temps throughout the whole mash. Heat rises, so maybe I'm worrying about nothing, but it does have me thinking. It is good that you're able to leave the lid on as that will retain heat.

Horsepuncher, leaving the lid off due to your mounting apparatus contributes to a ton of heat loss. I'd also worry about channeling with using a
Loc-line. All the wort flow is going back into that one spot. I'd try to make sure that your wort flow is just a bare trickle and there's a good inch or two of water above your grain bed.

I agree. The return hose needs to go to the top of the mash. That’s the only way you are truly recirculating.

 

[odie]

A 10 gallon kettle is bare minimum. And that’s only for standard beers

 

[ScrewyBrewer]

I recirculate wide open for the entire mash. It keeps mash temperature swings to a minimum, but uses energy the whole time.

 

[Jtvann]

I recirculate wide open for the entire mash. It keeps mash temperature swings to a minimum, but uses energy the whole time.

View attachment 659683

I think I just heard a LODO brewer scream from across the country seeing that sprayer.

 

[Cato1507]

I agree. The return hose needs to go to the top of the mash. That’s the only way you are truly recirculating.

True, I'm probably technically whirlpooling, but at 7gpm it keeps my temps right for me and my grain bed nice and fluid with no stuck sparge issues and little stratification. For me and my BIAB, I like it.
Since I've never recirculated from the top I'm not in the position to say yea or nay to that method.

 

[ScrewyBrewer]

I think I just heard a LODO brewer scream from across the country seeing that sprayer.

I'm sure you did. I've thought about purging the mash with Co2 and ended up doing closed transfers and replacing beer line with EVABarrier LODO lines for now.

 

[Wayne1]

There is no standard setting for mill gap. Every grain is different. Here is an excellent article from MoreBeer on mill gap settings for different grains: https://www.morebeer.com/articles/crushin_it

 

[MX1]

I have a High Gravity BIAB setup 15 gallon kettle with the typical craw-fish boil strainer basket and a BIAB bag.
I use a Chugger pump for all my water movement. I have no issues with re-circulation at all.

Let me say this: Don't let anyone tell you how to brew, if you want to re-circulate then do it! Change one thing at a time....loosen up your crush a mil or 2, see if that helps, if it does, make sure to check your efficiency.....rinse and repeat as needed.
Also, play with water-flow speed, i start slow, let the grain bed set, then ramp it up....IMHO it does not have to be full blast, but your system may react different....and I use a sprayer just like @ScrewyBrewer and don't give a whiff what the LODO cult says......

 

[odie]

MX1 sounds like yours is the same as mine. 15 gal kettle, steamer basket and a Wilser bag. But I'm still having problems with my recirc. specifically my really, really tiny pump will flow more than can naturally flow thru the grain bed by gravity so a huge air space develops below the basket and pretty soon the pump is pulling air thru bottom spigot and the pump starts to stall out. I've tried a false bottom to present more exposed surface area on the bottom of the bag but grain bed flow still can't keep up with the pump. Basically right now I'm having to cycle the pump on/off every 5-10 minutes.

 

[odie]

Or is my crush too tight? Is that even possible with BIAB? What I mean is maybe crush more "normal" and just mash longer to achieve BIAB efficiency?