Mash Tun Temp

[mtnbkr79]

hello, i am a new member and this is my first post. thanks in advance for your time if you make it to this post.

i have done about a half dozen all grain batches to date and am looking for suggestions/feedback on my mash procedure.

i am using a rectangular coleman cooler with a homemade manifold. it does an excellent job holding temp. here are the steps i am following:
1 - boil all mash water
2 - add immediately to mash tun to pre-heat
3 - leave lid open and wait for temp to drop to desired temp
4 - add grain and stir well

i think that preheating the tun so much has really helped hold my mash temp but i am having trouble figuring out what temp i should wait for the water to fall to before adding the grain. i have read to expect a 10 degree F drop in water temp but i am seeing more like 6-7. i am not using any homebrew software but was wondering if anyone has ever used a similar procedure for heating the tun as equipment temp seems to fall out of the picture.

 

[buzzkill]

I put grains in at 160, then stir like mad then check temp,if its high I stir more.

 

[mtnbkr79]

my last batch i tried 165, i was thinking of trying 160. probably will. do you see a consistent drop?

 

[Doc Robinson]

There are other variables involved such as grain volume, grain temperature, ambient temperature, etc. I experimented with my mash tun at 4 different temperatures to determine what the temperature loss to the mash tun (added 3.25 gallons 150, 160, 170, & 180 degree water to the tun). Now I know that if I heat 3.25g of water to 170 (typical for 10 pounds of grain), I will lose 8 degrees to the mash tun.

I use this calculator to determine my strike temperature and add my mash tun heat loss to the total...that is what I heat my mash water to.

http://www.brew365.com/mash_sparge_water_calculator.php

 

[devaspawn]

I would definitely use a mash calculator at the least. Beersmith or Beertools would be very helpful as you could customize it to your brewing process and conditions to help you better ascertain your mash temp (among many other things) no matter how big or small your grain bill is.

One other suggestion for your mash tun - that lid is hollow. Drill holes in the top of it, go to home depot or lowe's and pick up a can of great stuff, and then fill the lid to overflowing with that insulation. DO NOT try to wipe the excess off before it dries. Once it dries you should be able to pop off the excess or at the very worst cut it off with a boxcutter. Since I did this with my cooler I haven't lost even one degree in the 75+ brews I've done when mashing.

 

[Doc Robinson]

One other suggestion for your mash tun - that lid is hollow. Drill holes in the top of it, go to home depot or lowe's and pick up a can of great stuff, and then fill the lid to overflowing with that insulation. DO NOT try to wipe the excess off before it dries. Once it dries you should be able to pop off the excess or at the very worst cut it off with a boxcutter. Since I did this with my cooler I haven't lost even one degree in the 75+ brews I've done when mashing.

Kick ass idea.

 

[Lodovico]

+1 on Beersmith. You'll thank yourself everytime you brew.

 

[NYCHomebrewer]

One thing I noticed is that I lose a lot more heat with beers with relatively small grain bills then those with large grain bills.

My first batch was a simple ESB. I overshot my target temp by about 4 degrees on mash in, but ended up considerably below. The next batch I brewed was an "Imperial" Irish Red with a relatively high grain bill. Thinking I would benefit from my previous experience, I paid closer attention to the temp of the mash water and still overshot by two degrees. Not to worry I thought! I had prepared this time. Rather than fill my lid with foam, I had cut out a perfectly round piece of that silver/bubblewrap insulation to fit inside my cooler directly on top of the mash. The stuff reflects nearly 96% of heat. I punched a small hole through the center in which to set my thermometer, and I didn't lose a single degree of heat. Which of course, meant that my mash was two degrees warmer than ideal the whole time.

I have it just about zeroed in now, and the silver/bubblewrap stuff is awsome. Can't recommend it strongly enough. It helps my 7.5 gallons get to boiling temp on an electric stove and it keeps the mash temp loss at nearly zero.

NYCHomebrewer

 

[mtnbkr79]

i usually wrap my tun in a thick quilt during the mash and definitely notice the hot spot on the lid when i unwrap. i will be filling the lid with insulation this weekend! my typical temp loss over an hour is 2-3 degrees F with the quilt.

thanks for the cal link, i will be using that for sure. it looks like they have an iphone app as well.

 

[Doc Robinson]

i usually wrap my tun in a thick quilt during the mash and definitely notice the hot spot on the lid when i unwrap. i will be filling the lid with insulation this weekend! my typical temp loss over an hour is 2-3 degrees F with the quilt.

thanks for the cal link, i will be using that for sure. it looks like they have an iphone app as well.

I just filled my lid up with spray foam tonight. I can't wait to test it out.

 

[devaspawn]

When my son isn't here, I don't have the heat on. I've had the room temp be in the low 50's and not noticed ANY drop in temp during my mash. Great Stuff is GREAT!!!

 

[Brew-boy]

I use Beer tools Pro no need to pre heat the tun in my case. It had me calibrate my tun using it's procedure and now it is spot on. I just tell it what the temp of my garage is that day and I am usually within 1 degree of target.