Newbie Question Regarding Water Temperature Regulation

[lhommedieu]

I'm about to do my second all-grain brew. I've got a Bayou stainless steel pot that I use with my Bayou burner to provide my mash and sparge water. I've got a three-tier gravity system using the pot as the boil kettle/hot water tun, and two 5 gallon round insulated coolers. I'm putting a Blichmann thermometer on my pot before brew day.

My system so far has been:

1. Mash in by heating water in pot and transferring to mash tun. Let steep.
2. Lauter by heating water in pot, transferring to lauter tun, and then run the lauter tun water to the mash tun; wort from mash tun runs to brew pot.
3. Full boil with brew pot; chill and transfer to fermenter.

What is the best way to bring the hot water tun water to the proper temperature and to maintain it while I'm mashing in and lautering?

For example, if I'm mashing in from pot to cooler at @170 to bring the mash to @152, should I bring the water in the pot up to 170 and then adjust the burner to hold that temperature? Bring it slightly higher than 170 and then let it fall? I am guessing that there is a balance between heat loss from the pot to the colder air around it, and the heat going in from the burner. Or is this just nonsensical: the water is going in so quickly that I won't lose any temperature while I'm stirring the mash? For sparging the hot water is going from the pot to the second cooler at @168, and from there to the mash tun and from there to the now empty pot - but this case is different since the coolers are insulated.

Something tells me that this is really a lot simpler than I think it is...

Best,

Steve

 

[mcelrokj]

My setup is almost exactly what you've described. I am through about 15 all grain brews in a little over a year, here are my experiences on water temps...

First of all, I use THIS website to figure out what temp to get my water to before mashing in. It is usually pretty accurate. I make sure that my cooler and grains are the same temp (room temp) each time.

For my sparge, it took me several batches of low original gravity to realize I was underheating my sparge water significantly. I know a lot of people out there stress that you don't want to get your grains above 170F. I've found that to be somewhat of a myth. I heat my sparge water to near boiling, transfer into my HLT, and sparge. It's over 170, probably more like 180-190ish but seems to extract very well, and I have yet to notice any significant tannin extraction from it. It is better to overshoot your sparge than to sparge with cooler water, your efficiency will suffer.

In the end, if you miss your mash temp by 1 or 2 degrees, your beer is not ruined. It will be just fine. 3-4 degrees, and you may end up with a slightly drier/sweeter final product than anticipated, but again, your beer will still be fine. I think the biggest issue for me was getting my efficiency rates up. I was in the 60% range when I started, and I am now consistently in the 75-80% range.

 

[lhommedieu]

Thanks for your help. Since maintaining my fermentation temps helped enormously during my last brew, I figured that the next logical step would be to be more precise with my hot water tun by attaching a thermometer and transferring the water to the mash tun when I hit the temperature that I wanted. It's not necessarily more accurate than a floating thermometer but seems like it would be more convenient to read.

I read somewhere on this forum that taking three temperature readings from different places and averaging the result after stirring the mash really well gives you a pretty accurate reading, so if the strike water temperature in relation to the mash bill is accurate, then I should hit the temperature that I want for mashing. I realize that a good part of this is just learning how your equipment operates and then adjusting for effect. So, for example, if my strike water temperature gives me a different mash temperature for the specific grain bill/equipment that I'm using, then I'll adjust up or down using a little hot or cold water, and take notes for the next time.

I've been playing with the idea of adding a thermometer to my mash tun, but I don't think that I'm going to lose more than a degree or two in summer weather in an insulated cooler, so what would be the point? Taking the temperature of the mash just before I sparge as per the above will settle the issue anyway - and then I can adjust for the next time that I brew.

 

[lhommedieu]

Just a follow-up:

Thinking my process out loud and hoping that someone will give me some feedback if I haven't thought things through.

I ended up getting a variable length bulkhead and digital thermometer kit from http://www.brewhardware.com/ to measure my mash temps from the middle of the cooler. I'm curious to see how convenient this is for getting to a correct mash temperature, and for measuring how much temperature I lose over a 60 - 90 minute mash. Since I brew outside I suspect that I'll need some kind of insulation system for the colder months, but we'll see.

I plan to bring my strike water to just above the recommended temperature and let it fall down to where I need it, adjusting the flame under the pot as needed to maintain the temperature, and add the water to the mash tun while adding mash, and stirring continuously. If at the end of the process the thermometer in the middle of the mash tun reads the temperature that I want, then I'll close the mash tun and let it sit. If I need to adjust at this point then I'll keep stirring and add hot/cold water as needed.

My grain bill/water for the brew that I want to make does not leave a lot of head space in a 5 gallon cooler; when I start using 10 gallon coolers for darker/heavier beers then I'll probably start insulating the head space, if necessary.

 

[Yooper]

I would suggest adding the strike water to the cooler very warm- 180 degrees- and then covering them and letting the cooler preheat while the temperature drops to the strike temperature. That will really help maintain temperature for the mash. You'll notice that the water will drop 10 degrees very quickly, and then level off. Wait until your water is the proper strike temperature (generally about 11 degrees above the desired mash temperature) and then add your grain.

 

[lhommedieu]

Thanks for letting me think out loud here. On a digital note card on my desktop is a cut and paste quote (probably yours) that gives me the same advice. I'll follow through and let you know how it went.

Thanks.

Steve

 

[oakbarn]

I use the Brew Math App on the Iphone. The Stike Temp is Right On. We used to always be just a little high and then would add cooling water to get to temp, close the lid a wait. Worked great. Finally took the plunge and added at the Brew Math Strike Temp, and Mash was exact.


I would suggest that you have the Mash Tun water at you desired temp prior to adding the grain. Also much easier to cool than heat. You just have to add a minimum amount of Cooling water but seems to add gallons of boiling water to raise the Mash (form our BAD!).