False Bottom Stuck Sparge Woes

[HeavyKettleBrewing]

Yesterday was my second trial run as I develop my future brew stand. I recently changed out to a 10gal round cooler for an MLT and installed a domed false bottom. Runnings were very slow on the first day and yesterday was hell having experienced a stuck sparge Satan would be proud of. Changed the dynamics of my brew day! It seems as though the grain is actually wedging itself into the perforations in the false bottom restricting flow almost completely. I believe this is the cause. I am using thickwalled silicone hose from false bottom to ball valve inlet. It is not collapsing in on itself. I understand that the crush may be too fine. Service provided by LHBS. They own the brewery adjacent to the brew shop so I have never questioned their gap setting.

Any one have a similar problem and solution? Any of the vendors have advice?
Thanks in advance.

 

[Bobby_M]

You have to watch that center fitting on the false bottom. If the FB flexes a bit under the suction, that fitting can bottom out and seal tight to the bottom of the cooler. Cutting some slots or otherwise supporting it off the bottom will help.

 

[day_trippr]

Grain bill? Mash water/grain ratio? Vorlauf procedure?

Some grains are "sticker" than others, low water/grain ratios don't help, and kicking off a vorlauf too fast can hopelessly jam up both FBs and braids...

Cheers!

 

[big_al_in_k-zoo]

+1 to what Bobby said. I used to have same problem as you, so I cut with my angle grinder a "notch" into the bottom of my copper pickup so that if it gets pushed down it can still flow. Haven't had a problem since. I have keggle mash tun w\ jaybird false bottom and re-circ via pump and RIMS.

 

[TrickyDick]

I had issues with my plastic insulated cooler mash tun.

The easy answer is get or build a bazooka screen.

Issue 1 is these coolers aren't designed for hot liquids, and over time the adhesive breaks down and the inner lining will separate from the insulation. When it does you will lose your seal with a false bottom and be sucking grain. Because you won't be able to see it, you won't know what happening.

issue 2. Can't be (easily) heated. At least not directly, unless your injecting steam.

Issue 3. Easy to knock stuff (tubing connections) off the false bottom while stirring or to upset it from the seal.

One you fix the problem you're having now by either supporting the outlet side below the false bottom or by switching to a bazooka screen, you will eventually run into problem above.

I know people love their coolers, and I used to be in that crowd. Fact is that mash times are often (for most single infusion mashes) far longer than they need to be for complete conversion. stone brewing supposedly does 10-15 min mashes for at least some brews if not all. Temp stability in an insulated cooler is a plus, but probably not as big of a plus as people think given that most are mashing longer than necessary. I now use a direct fired mash tun with a false bottom. Works great. Solves all my problems.
Good luck.

TD

 

[HeavyKettleBrewing]

You have to watch that center fitting on the false bottom. If the FB flexes a bit under the suction, that fitting can bottom out and seal tight to the bottom of the cooler. Cutting some slots or otherwise supporting it off the bottom will help.

Here's the kicker, I attached a coupler to the elbow on the false bottom to minimize my deadspace. I never thought about the sucker (no pun intended) flexing on me. I measured a 5/16" gap between coupler face and FB diameter. The cooler is most likely not flat at the center bottom making the gap even smaller. I'll just take it out and slot it with a cuttoff wheel or use silicon tubing around the diameter of the FB to kick it up a bit. I did not think to mention this as the FB seems quite sturdy. Thanks for the input.

 

[HeavyKettleBrewing]

I had issues with my plastic insulated cooler mash tun.

The easy answer is get or build a bazooka screen.

Issue 1 is these coolers aren't designed for hot liquids, and over time the adhesive breaks down and the inner lining will separate from the insulation. When it does you will lose your seal with a false bottom and be sucking grain. Because you won't be able to see it, you won't know what happening.

issue 2. Can't be (easily) heated. At least not directly, unless your injecting steam.

Issue 3. Easy to knock stuff (tubing connections) off the false bottom while stirring or to upset it from the seal.

One you fix the problem you're having now by either supporting the outlet side below the false bottom or by switching to a bazooka screen, you will eventually run into problem above.

I know people love their coolers, and I used to be in that crowd. Fact is that mash times are often (for most single infusion mashes) far longer than they need to be for complete conversion. stone brewing supposedly does 10-15 min mashes for at least some brews if not all. Temp stability in an insulated cooler is a plus, but probably not as big of a plus as people think given that most are mashing longer than necessary. I now use a direct fired mash tun with a false bottom. Works great. Solves all my problems.
Good luck.

TD

I am in the R&D process of designing an affordable setup. Once I get the basic unit down, I will consider a single tier multi burner setup. I agree with the mash times you stated above. Never used a false bottom before so I will learn as I go. All advice is appreciated.

 

[TrickyDick]

I am in the R&D process of designing an affordable setup. Once I get the basic unit down, I will consider a single tier multi burner setup. I agree with the mash times you stated above. Never used a false bottom before so I will learn as I go. All advice is appreciated.

I'd seriously consider just swapping the FB off, and putting a bazooka screen on. I had nothing but problems when I went AG, and I attribute many problems to the insulated cooler/false bottom combo. I was a very happy man when I discovered what the problem was and switched to a bazooka screen. Generally cheaper as well compared to a false bottom. I brewed a huge Belgian dark strong ale in the 10 gal mash tun using a step mash steam injection setup. Tun was full to within 1". When I ran off the wort I had valve wide open and no sticking. I did batch sparge then. Anyway, that bazooka branded screen was very strong and I however had issue with it collapsing or clogging.

TD

 

[hunter_le five]

Try adding rice hulls to the mash.

 

[HeavyKettleBrewing]

Try adding rice hulls to the mash.

If I cannot remedy the problem by notching the bottom of my pickup, I will imagine that rice hulls will be the next step. I would hate to change out the FB with a bazooka screen but may be forced to consider it if problem persists.

 

[drMT]

A bazooka screen dramatically decreased my efficiency...10% or more.

 

[TrickyDick]

A bazooka screen dramatically decreased my efficiency...10% or more.

What was your efficiency before and what kind of gear were you using before switching to bazooka? Is it the official Bazooka or another type or homemade? Can you snap a picture?
What type of mash tun do you use and what type of sparge do you perform?
Do you double crush?

TD

 

[drMT]

I need to ammend my first statement. After further research, I have determined that the grain bed depth was the culprit along with the screen not reaching across the cooler. I had recently switched from a round 10 gal rubbermaid to a rectangular 17 gal cooler. With the increased size my grain bed depth decreased dramatically for 5 gal batches. Also the screen did not run the length of the cooler so I believe it contributed to uneven flow and therefore lowered efficiency of yield.
I have since gone back to the 10 gal rubbermaid and used the bazooka screen (from my LHBS), which I bent slightly to fit, and my gravities have been spot on.

 

[CGVT]

A very simple inexpensive fix is to buy a stainless steel scrubbing pad and put it under the false bottom at the pick up tube. If the FB is collapsing the scrubby will keep the pickup from bottoming out. If grain is getting through the FB and into the pickup tube, the scrubbing pad acts as second strainer and keeps grain from getting into the tube.

I went to this on my mash tun and have not had a stuck mash or sparge since.

 

[pmsjr]

A very simple inexpensive fix is to buy a stainless steel scrubbing pad and put it under the false bottom at the pick up tube. If the FB is collapsing the scrubby will keep the pickup from bottoming out. If grain is getting through the FB and into the pickup tube, the scrubbing pad acts as second strainer and keeps grain from getting into the tube.

I went to this on my mash tun and have not had a stuck mash or sparge since.

CGVT, sorry to resurrect an old post, but is that stainless pad still working out for you? In my case I don't think it's the FB flexing as much as the bottom of the cooler growing upward when heated, leading to a seal with my FB suction. Did you use the "chainmail" type of pad, or one of the stainless pads that more resembles "steel wool"?

Thanks.