Brewing Equipment

[Aussiekraut]

I think I finally figured out my issues with the BrewZilla. I seem to have a problem working out numbers and now I know why I seem to miss the boil off rate I measured with water. It is all in the design of the device. At the bottom of the vessel is a screen, which is designed to let wort through but keep break and grain bits back and as such make cleaner wort. But this Emu Evita ly leads to issues with the temperature sensor getting accurate readings. I have installed a heat deflector plate, which is attached underneath the screen. This helps during mash but seems to exacerbate things when it comes to boil. Break and debris from the mash settle at the bottom, completely covering the screen. Because of the deflector, the only place wort can get through is the side of the screen. So in essence, whatever is underneath the screen is being boiled, drops to 99.7, gets boiled again and so on. Not much of this action makes it to the top of the vessel. When the break is scraped with a paddle and all is given a vigorous stir, all the while the recirc pump is running, the temperature can drop right down to the 97s. Things never boil enough to reduce volume enough. So I need a thermometer that can talk to the BrewZilla and overrides the built in sensor.

[Red devil 44]

New addition to the bar area, had some primer, spray paint, little handy work down the bottom and what do you know, a Sharkies stubby cooler dispenser.

Up Up Cronulla !! 

[Shamus O'Sean]

7 hours ago, Aussiekraut said:

I think I finally figured out my issues with the BrewZilla. I seem to have a problem working out numbers and now I know why I seem to miss the boil off rate I measured with water. It is all in the design of the device. At the bottom of the vessel is a screen, which is designed to let wort through but keep break and grain bits back and as such make cleaner wort. But this Emu Evita ly leads to issues with the temperature sensor getting accurate readings. I have installed a heat deflector plate, which is attached underneath the screen. This helps during mash but seems to exacerbate things when it comes to boil. Break and debris from the mash settle at the bottom, completely covering the screen. Because of the deflector, the only place wort can get through is the side of the screen. So in essence, whatever is underneath the screen is being boiled, drops to 99.7, gets boiled again and so on. Not much of this action makes it to the top of the vessel. When the break is scraped with a paddle and all is given a vigorous stir, all the while the recirc pump is running, the temperature can drop right down to the 97s. Things never boil enough to reduce volume enough. So I need a thermometer that can talk to the BrewZilla and overrides the built in sensor.

I did wonder about this type of issue with the Brewzilla.  I similarly bought a Brewzilla 35L False Bottom with feet for use in my Grainfather G30.  The expectation was it would capture more of the brewing trub and protect the standard Grainfather G30 hop filter.  I only used it for a couple of brews because the boil caused it to lift and twist and rattle around allowing plenty of trub to get underneath it anyway.  

This may not be an issue for the current Brewzilla because isn't the new false bottom held in place reasonably well?  Which might be part of your issue, with the "super" boiling under the false bottom.  Maybe the deflector plate is more hassle than help.

[Aussiekraut]

10 hours ago, Shamus O'Sean said:

I did wonder about this type of issue with the Brewzilla.  I similarly bought a Brewzilla 35L False Bottom with feet for use in my Grainfather G30.  The expectation was it would capture more of the brewing trub and protect the standard Grainfather G30 hop filter.  I only used it for a couple of brews because the boil caused it to lift and twist and rattle around allowing plenty of trub to get underneath it anyway.  

This may not be an issue for the current Brewzilla because isn't the new false bottom held in place reasonably well?  Which might be part of your issue, with the "super" boiling under the false bottom.  Maybe the deflector plate is more hassle than help.

The deflector seems to help with better temperature distribution but affects the flow of liquid a little. I guess if there is trub on the screen, it acts like a bit of an insulator. On the other hand, trub on the heaters like I had in the Guten didn't seem to cause any drama. Liquid can get through and past suitably well but the heat can't by the look of it. I even go as far as using the recirculation pump throughout the boil. This helps a little but I still need to stir the wort vigorously every few minutes to get meaningful heat distribution. 

There is a video on the Homebrew Network where Gash addresses issues getting steady temperatures in the BZ4. One solution is to use an external thermometer that can be configured to override the built-in temp sensor. I think if the temperature information came from the centre of the kettle, it'd be much better. At this point during boil, it sits at 100C, drops to 99.9, 8, 7, 8 9 100. All within about 10 seconds. However, it can get over 100C as well. Yesterday I saw this. The second photo was taken immediately after a vigorous stir and a little scape on the bottom screen. Literally, less than 30 seconds apart.

 

[Shamus O'Sean]

12 hours ago, Aussiekraut said:

The deflector seems to help with better temperature distribution but affects the flow of liquid a little. I guess if there is trub on the screen, it acts like a bit of an insulator. On the other hand, trub on the heaters like I had in the Guten didn't seem to cause any drama. Liquid can get through and past suitably well but the heat can't by the look of it. I even go as far as using the recirculation pump throughout the boil. This helps a little but I still need to stir the wort vigorously every few minutes to get meaningful heat distribution. 

There is a video on the Homebrew Network where Gash addresses issues getting steady temperatures in the BZ4. One solution is to use an external thermometer that can be configured to override the built-in temp sensor. I think if the temperature information came from the centre of the kettle, it'd be much better. At this point during boil, it sits at 100C, drops to 99.9, 8, 7, 8 9 100. All within about 10 seconds. However, it can get over 100C as well. Yesterday I saw this. The second photo was taken immediately after a vigorous stir and a little scape on the bottom screen. Literally, less than 30 seconds apart.

 

Hmm.  Interesting.  The surface looks pretty flat, like not much boiling activity.  While the deflector plate might help with better temperature distribution during the mash, it seems like it is a hinderance during the boil.  I understood the idea of the deflector plate pushing the recirculating liquid to the outside of the kettle, so it had to pass the concealed heating element on its way to the central outlet.  However, I did think if the water is recirculating reasonably well during the mash, the mash temperature would still be reasonably stable.  Well, at least stable enough to make beer.

I suppose if the boil is around the appropriate temperature, it will still sterilise the wort, deal with DMS, increase the SG, and do whatever else it is meant to achieve.  However, my thinking, not having used the Brewzilla, would be to loose the deflector plate.  Alternatively, as you suggest, get the RAPT temperature probe so the boil is managed by the temperature higher up in the kettle.

[Aussiekraut]

Soooo I have used the RAPT thermometer with the BrewZilla today. I had to fiddle with a few settings but now the system responds to the temperature in the kettle and not below the bottom screen and deflector plate. Today's batch was probably not the best candidate to showcase things but then again, things went quite well. I brewed a Wheatwine today and this kind of recipe does pose its challenges. I should have mashed with more water and had some fairly sad results from the mash but my main focus was the boil. With the RAPT thermometer set to be the authority, I did for the first time since I used the BrewZilla, get a rolling boil. Actually quite a ferocious boil. I hit my 4l boiloff rate based on plain water testing. I still got some discrepancies in temperature and when the gap was too big, got some odd behaviour but all in all, it is a vast improvement. Next brew, I will remove the deflector plate and then we'll see how things go. 50 bucks well spent but then again, buying a $900 system, I really shouldn't have to spend the extra dosh. Well, if it all works for me now, I'll be pleased. It took me quite some time to get used to the BrewZilla and I'm still learning. 

[Foam Flecked]

1 hour ago, Aussiekraut said:

quite a ferocious boil.

@Aussiekraut - try setting the target temp higher than 100C and regulate the boil by reducing the wattage if necessary. I've found that the internal sensor in my kit is over-reading by a couple of degrees compared to the RAPT thermometer. You can see in your photos that the heat is off in the first one at 101.2 when it doesn't need to be.