Hi all, long time lurker first time poster here. So I've been running my triple 15 gallon SS Brewtech kettles for 7 or 8 brews now and have been finding my efficiency won't really improve on 65% mash efficiency. Now one thing I have noticed is that the mash tun does seem to lose temp over the 1 hour single infusion mash. The tun itself is a single layer of space blanket insulation, around a 15 gallon SS Brewtech kettle, and have been finding the mash temp drops by 2-3 degrees over the mash. I guess my question is, am I better in swapping this out for the 10 gallon fully insulated tun either from brewbuilder or SS Brewtech or would the use of a RIMS or Herms system be of better use. I'd prefer not to bosh holes in my kettles but if needed I can. I know I shouldn't be chasing efficiency but it's a nice benchmark to improve upon. Any advice is welcome.
Maintaining Mash Temps
- Thread starter vexedben
- Start date
Help Support The Homebrew Forum:
2-3 degrees isn't a particularly big enough drop to worry about given that most of the conversion happens in the first half hour and assuming you're mashing in at 65-68C. You could wrap it an old sleeping bag or quilt tied up with a couple of ropes if you want a cheap way to improve the insulation.
To improve mash efficiency the first place I'd look is the grain crush size, then how well you're sparging and finally the thickness of the mash if you're brewing the 3 vessel style.
To improve mash efficiency the first place I'd look is the grain crush size, then how well you're sparging and finally the thickness of the mash if you're brewing the 3 vessel style.
As Foxbat says you temp drop doesn't look too bad.
However I have just put some of this around my mash tun and it holds the heat in much better than the space blanket stuff. I used 5mm thickness but had enough to to do double thickness so a 10mm thickness would be better.
https://www.efoam.co.uk/zotefoam-plastazote.php
However I have just put some of this around my mash tun and it holds the heat in much better than the space blanket stuff. I used 5mm thickness but had enough to to do double thickness so a 10mm thickness would be better.
https://www.efoam.co.uk/zotefoam-plastazote.php
In terms of grain crush I've been buying malts pre crushed from suppliers who buy direct from crisp. Is the traditional crush size a bit on the coarse side then? I presume the crush size in this case, doesn't scale too well with home brewery sizes? I've tried fine crush from the malt miller, but did end up with a stuck mash when I did mind. Potentially sparged too quickly.
I'm terms of sparging I'm using the Brewtech recirc manifold, but do have a spray ball on order to try that as an alternative to effectively hit the grain bed and hopefully reduce any channeling that may be happening. Normally I try for 40 minutes of sparging.
I'm terms of sparging I'm using the Brewtech recirc manifold, but do have a spray ball on order to try that as an alternative to effectively hit the grain bed and hopefully reduce any channeling that may be happening. Normally I try for 40 minutes of sparging.
Are you recirculating during the mash? it certainly does increase the efficiency 
On the assumption that you are recirculating, what about running your recirculation circuit through a coil of copper pipe immersed in one of your kettles, set to the mash temp?
Alternatively I do a simple HERMS by using my counterflow chiller as a heat exchanger: pumping my wort recirculation circuit through one way, and temperature controlled water through the other. This easily offsets the heat lost from the mash tun (and also allows me to do a step mash when I want).
It wasn't expensive to make - just a cheap 12v pump (about £10) and a kettle hooked up to a PID controller to provide the hot water. It does of course require a counterflow chiller that can handle the mash temps (mine's made from silicone hose and 8mm copper microbore heating tubing), but from the looks of your setup I'm guessing you might have a metal plate chiller you can use?
On the assumption that you are recirculating, what about running your recirculation circuit through a coil of copper pipe immersed in one of your kettles, set to the mash temp?
Alternatively I do a simple HERMS by using my counterflow chiller as a heat exchanger: pumping my wort recirculation circuit through one way, and temperature controlled water through the other. This easily offsets the heat lost from the mash tun (and also allows me to do a step mash when I want).
It wasn't expensive to make - just a cheap 12v pump (about £10) and a kettle hooked up to a PID controller to provide the hot water. It does of course require a counterflow chiller that can handle the mash temps (mine's made from silicone hose and 8mm copper microbore heating tubing), but from the looks of your setup I'm guessing you might have a metal plate chiller you can use?
Last edited:
![BREWING THERMOMETER STICKERS ACCURATELY MONITOR FERMENTING BEER & WINE LIQUID TEMPERATURES 5PCS HOME BREW SPIRITS WINE LCD ADHESIVE [US]](https://m.media-amazon.com/images/I/311DDjo2X3L._SL500_.jpg)
You haven’t told us much detail about your mash process but for what it’s worth I do the mash in bit at the start, getting rid of lumps etc. and stir the mash a further 2 times each after 15 minutes. I recirculate my wort as @The-Engineer-That-Brews mentions. I built a HERMS tank from a small waste bin..
...fitted with a copper coil through which the wort is pumped. The bin is fitted with a kettle element, that is temperature controlled, and filled with water.
When it comes to sparging, I don’t technically sparge (I think). I do 2 mini mashes, so after I’ve drained the wort from the (first) mash I refill the mash tun and circulate for 30 minutes, stirring once. Drain the wort and repeat.
...fitted with a copper coil through which the wort is pumped. The bin is fitted with a kettle element, that is temperature controlled, and filled with water.
When it comes to sparging, I don’t technically sparge (I think). I do 2 mini mashes, so after I’ve drained the wort from the (first) mash I refill the mash tun and circulate for 30 minutes, stirring once. Drain the wort and repeat.
A double batch sparge, I believe...
- Joined
- Nov 13, 2013
- Messages
- 6,852
- Reaction score
- 7,038
Most of your heat loss will be going out of the top. Get some polystyrene 75mm thick cut it to the dia of your mash tun, wrap some alfoil around it and float it on the top of your mash.
Don't worry about efficiency, the efficiency will be what it is, as Ned Kelly said, "Such is life"
Re circulating is intended for sustaining mash temperature throughout the mash, doesn't help if you haven't got a heat source inside the mash tun.
I did my early mashes in an esky using the polystyrene and it worked well, as others have said blankets or an old doona wrapped around keeps that heat in there.
Don't worry about efficiency, the efficiency will be what it is, as Ned Kelly said, "Such is life"
Re circulating is intended for sustaining mash temperature throughout the mash, doesn't help if you haven't got a heat source inside the mash tun.
I did my early mashes in an esky using the polystyrene and it worked well, as others have said blankets or an old doona wrapped around keeps that heat in there.
At the moment my mash is pretty basic, underlet with the strike water, give it a good old stir and then leave the lid on. I'd love to recirculate but that is when I saw a massive temp drop, which I put down to the silicone hose.
The little Herms kits sound like a good idea, I've got an inkbird PID laying about so would just need some bits to create the coil and heat exchange. I was doing some research last night and came across an asparagus pot and coil combo.
Thanks for the tips so far guys, hopefully I can report back when I've got a solution.
The little Herms kits sound like a good idea, I've got an inkbird PID laying about so would just need some bits to create the coil and heat exchange. I was doing some research last night and came across an asparagus pot and coil combo.
Thanks for the tips so far guys, hopefully I can report back when I've got a solution.
Highly unlikely... the thermal mass of the hose will be absolutely negligible compared to that of the wort. Sounds more likely that it's due to the cold wort near the sides being mixed back in.
Either way I'd say you definitely need to recirculate if you can and your 'asparagus pot and coil combo' sounds ideal. Might even be able to cook asparagus at the same time ;-)
If you can’t find a suitably sized former to make your coil, I made a video on how to make your own pipe bender to produce a coil of any diameter, big or small.....
Blimey that's clever! What diameter copper pipe is that? I used the 8mm stuff (£17 for 10m from ScrewFix: link)
Similar threads
