stainless mash tun and temperature stability

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woopig

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I've finally decided on getting a stainless mash tun. I keep reading about people insulating their mash tuns in various ways, and I'm wondering how much of an issue temp stability really is. Even if I invest in a nice one such as a MegaPot or something similar, should I expect my temps to be all over the place? Thanks
 
I've finally decided on getting a stainless mash tun. I keep reading about people insulating their mash tuns in various ways, and I'm wondering how much of an issue temp stability really is. Even if I invest in a nice one such as a MegaPot or something similar, should I expect my temps to be all over the place? Thanks

Lots of guys who use kettles or keggles for mash tuns make use of a RIMS heat exchanger or HERMS heat exchanger to keep the Mash tun temperature stable. If you don't plan on direct heating or using a heat exchanger on your mash tun you should insulate it or use a cooler as a mash tun as it will cool down pretty quickly depending on the temperature of the environment in which you are brewing.
 
Thanks, Guy.

I should have clarified that point. I was planning on keeping it simple and just direct-heating the mash tun for now. However, I was hoping I wouldn't have the problem I'm currently having with my mini-mash procedure.

I use a cheap aluminum stockpot, and I'm constantly having to turn the burner off and on to stay within range. I don't even mind doing that, it's just that when it gets low (say 140 or so), almost as soon as I fire it up I'm overshooting and at 170. I figure precision temp control isn't as important in mini-mash and steeping, but was hoping I could stay a little more stable when I step up to all grain.
 
Thanks, Guy.

I should have clarified that point. I was planning on keeping it simple and just direct-heating the mash tun for now. However, I was hoping I wouldn't have the problem I'm currently having with my mini-mash procedure.

I use a cheap aluminum stockpot, and I'm constantly having to turn the burner off and on to stay within range. I don't even mind doing that, it's just that when it gets low (say 140 or so), almost as soon as I fire it up I'm overshooting and at 170. I figure precision temp control isn't as important in mini-mash and steeping, but was hoping I could stay a little more stable when I step up to all grain.

When you do step up to all grain get yourself a copper coil, a cheap PID, a thermistor or RTD and a pump. You can make an inexpensive HERMS and you will never have to worry about your MLT temperatures again.
 
How about recirculating your mash while you are heating it with a pump? I set my flame very low and recirculate while heating to keep from scorching under the false bottom. Once you have done it enough you will learn your system and know when to shut it off to hit your target temp.
 
Thanks, Guy.

I should have clarified that point. I was planning on keeping it simple and just direct-heating the mash tun for now. However, I was hoping I wouldn't have the problem I'm currently having with my mini-mash procedure.

The only problem with doing it that way is that it doesn't work very well. I tried that approach thinking that it would be simple and effective. It's not. Worse yet, if you are using a false bottom, there is no way to stir the wort below it. You can do a manual recirculation, but that is a lot of work and gets very old very fast. Additionally, if you are not using a false bottom, but a braid or manifold instead, the grain itself is at risk of scorching. I'm guessing you are thinking almost exactly as I was when I first began all grain brewing. It would seem to be easy to heat the MT and keep it at a controllable stable temperature and no problem to ramp up temps when needed. Unfortunately, that's not the case as you are about to find out. IMO, controlling mash temperatures is critical to making top notch beer. Temperature control is very important for both the mash and fermentation. I'm currently running a semi-automatic direct gas fired RIMS and it's working very well for me, but it didn't happen overnight either. Good luck with your brewing. Post back and let us know how things progress.
 
I'm with Catt here. I would not advocate a direct fire metal tun unless you're willing to buy a pump and enact some form of automated temp maintenance. You just do not get the bang for the buck that you will in a well insulated cooler. It's not a shiny but you can always wrap your cooler in diamondplate if you want.
 
Thanks, Guy.

I should have clarified that point. I was planning on keeping it simple and just direct-heating the mash tun for now. However, I was hoping I wouldn't have the problem I'm currently having with my mini-mash procedure.

I use a cheap aluminum stockpot, and I'm constantly having to turn the burner off and on to stay within range. I don't even mind doing that, it's just that when it gets low (say 140 or so), almost as soon as I fire it up I'm overshooting and at 170. I figure precision temp control isn't as important in mini-mash and steeping, but was hoping I could stay a little more stable when I step up to all grain.

until you get a new system worked out, i'm assuming your stockpot is small enough to stick in the oven? preheat your oven to 150ish, then turn it off and your mash temps should stay pretty stable. imo, this is a better option for a mini-mash than turning a burner on and off.
 
Hey while we are on this subject (sorry if this is slightly off topic OP)....

What are the drawbacks to heating your strike water in your mash tun if you do have a stainless kettle? Seems to me this will help it stay at target temp longer.
 
Yep, that's the way I do it. I also just heat the strike water and dump the grain in all at once. Usually hit my target temps within one degree or dead on.
 
until you get a new system worked out, i'm assuming your stockpot is small enough to stick in the oven? preheat your oven to 150ish, then turn it off and your mash temps should stay pretty stable. imo, this is a better option for a mini-mash than turning a burner on and off.

This is excellent advice. I've used this method when doing a cereal mash and it worked very well.
 
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