Brewzilla mash temp question

[liams1989]

Hi all. Doing my first all grain, and I’m wondering if anyone knows how much of a difference there is between the temperature at the bottom where the probe is and the top especially when mashing. I’m supposed to have a mash temp of 65, however at the top of my brewzilla I’m hitting around the 60 mark but I’ve got the brewzilla set to 72. Is the probe temp going to be true based on the fact it’s so close to the element? Should I be even worrying about the temp at the top of the mash?
Thanks

 

[ssparks]

The probe is too close to the heating element so is not going to give a reasonable reference. Personally I measure the temp of the grain at the top with a digital probe as I can poke this through the screen and into the actual mash

 

[Rodcx500z]

Hi Liam, i mash in at 70 ish once mashed in i set temp at 67c for a temp of 65c, after 5 minutes i turn the pump on and recirculate i then wait 5 more mins and stick my digi probe in the tube were the wort comes from the pump, it normally reads 64.7 if not i turn the temp to 68c, this on a brewzilla 35L hopes this helps and good luck with the brew

 

[hoppyscotty]

The temp management on these things is a bit hit and miss. Most has have the temp sensor at the bottom and rely on good recirculation to manage the temperature down the depth of the mash pipe. The brew I did last weekend saw the temp at the bottom via the in-built sensor to be at mash temp of around 69 degrees, but had a slow/stuck mash and the temp at the top was in the high 50's so a good 10 degree temperature difference. OK was in the garage so pretty cold ambient temp, would have been less of a difference if I was brewing in a warmer environment.

I think recirulcaion and some overlfow is very important in regulating mash temp over the height of the malt pipe so if you have a slow or stuck mash then you're really going to struggle to have a consistent temperature over the entire height.

 

[The Baron]

Hoppyscptty is bang on you must recirculate during mash to get a reasonably even temperature during the mash. My Ace which is the same as the Klarstein/Angel brew/ Brew Monk etc has the probe at the bottom but is reasonably accurate with the the recirc pump on. Getting a even mash temp is virtually impossible so go for a temp check in the middle of the mash and take that as a average. It does not matter how expensive your system is it will always be slightly hotter at the bottom and cooler at the top.

 

[hoppyscotty]

I had thought about constructing a circular manifold out of copper pipe with 4 legs that go vertically down into the grain column so the recirculating wort is 'injected' at all heights in the grain stack. You could have more holes at the top of the legs so more wort is delivered towards the top of the grain stack to maximise recalculation, with less of the wort being 'injected' in the lower half mainly for temperature regulation. Might even help with prevention grain bed compaction and reduce chances of slow/stuck mash.

no idea if this would work or be effective but short of having heating elements pushed into the grain bed I can't think of another way of guaranteeing you get consistent temperature over the entire height.

 

[The Baron]

Do not overthink it or your head will explode take readings and average them out if you want to be more precise for me a middle mash reading will suffice. I find it hard to believe any brewer gets the mash with the same temp all the way through its like finding the holy grail. Just be satisfied you are as near in a average reading and take that, you are falling into the anal trap and as I have said it will explode your head instead of enjoying the brew day. Hope this helps

 

[foxy]

Hi all. Doing my first all grain, and I’m wondering if anyone knows how much of a difference there is between the temperature at the bottom where the probe is and the top especially when mashing. I’m supposed to have a mash temp of 65, however at the top of my brewzilla I’m hitting around the 60 mark but I’ve got the brewzilla set to 72. Is the probe temp going to be true based on the fact it’s so close to the element? Should I be even worrying about the temp at the top of the mash?
Thanks

The thicker the mash the motre temperature variant, stir the mash for a more consistant temperature. The probe is in the best position nearer the element anywhere else wouldn'tbe any good. Stirring is the best option raising temperature beneath the false bottom could start cooking the wort. They are working on new single vessel breweries now which heats with microwaves which gives the same temperature throughout the mash.

 

[Nicks90]

What about getting the strike temp right, stir it vigorously to ensure its all even and then wrap the vessel up with a good sleeping bag or fleece.
Should maintain a good constant temp without the need to apply heat and recirc and all that. Surely has to be simpler and more reliable.

 

[hoppyscotty]

Because we want the benefits of recirculation.

 

[foxy]

What about getting the strike temp right, stir it vigorously to ensure its all even and then wrap the vessel up with a good sleeping bag or fleece.
Should maintain a good constant temp without the need to apply heat and recirc and all that. Surely has to be simpler and more reliable.

I think that is the only way to mash, single infusion isothermal mash for most beers. A good esky with good insulation will achieve a better single mash temperature. The downside of recirculation is the heat lost. The upside of a single vessel brewery is it is easy, just the mash temperature can be all over the place without some agitation.

 

[Philthebrewer]

Foxy made a good point about the mash thickness. I always use the maximum water I can get in (25l in my 35l brewzilla) so that it is a thin mash which recirculates acceptably and has good heat conduction via the water in the mash.

You must measure the temp of the mash itself, not rely on the inbuilt thermometer. I barbcue probe (or 2) works just fine in my case.

 

[The Baron]

I have always been a believer in using a higher volume of water in my mash. As Foxy has said you have less chance of a consistent temperature with a thick mash, I use 20l in a kg grain bill as a rule and also you could maybe try some rice hulls/oat husks to aid flow through the mash too which will help with more consistency in temp

 

[Hop_it]

The advice given by The Baron (#7) is really sound. I got very frustrated with this issue last year, and got to the point of an . You have to accept that these machines are far from perfect in terms of control, but they are convenient in many other respects. However, there are a few things that you can do to help the circulation, which in turn helps to even out the temperature gradient:

• Try to create a thin(ish) mash and stir manually (already mentioned above).
• Some advocate removing the central recirculation tube from the malt pipe and blanking off the threaded hole in the base plate because it makes stirring easier. The possible downside is that there is no hot wort passing down the tube to reheat the mass of the mash. Suffice it to say that opinions will differ on this issue.
• Try to use a coarse grain crush because this will speed up circulation. The downside is that you might reduce efficiency if you go too far.
• Try to avoid brewing anything containing high levels of wheat/malted wheat, oats and rye until you get more familiar with the foibles of the Bz. It is very frustrating to get a stuck mash . You will be in a far better position to deal with it when you have a bit more experience with all-grain brewing.
• Rice hulls and oat hulls (also mentioned above) are also a means to improving flow through the mash, but be aware that they need to be washed thoroughly before using them in a brew. . . . . . . Just ask foxy for his opinion on using them :tinhat:
• Use some additional insulation to keep the overall temperature up (see photo attached)

Hope this helps, but don't despair because you will learn to tame the beast

 

[Gingerbrews]

Mine consistently reads 9°C over what my old fashioned thermometer reads. Was v frustrating initially but I've learned to live with it