# Help with water temps

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#### RJBanks

##### Well-Known Member
I am about to brew my first batch just using my 10 gallon Spike kettles. I have always used coolers for my HLT and mash but I now have a brew stand.

Can anyone help with how much I have to heat 6.7 gallons of water in HLT so when I add my grains, 15 pounds, to the mash tun the temp drops to around 150 degrees?

#### hotbeer

##### Opinionated Newb
HBT Supporter
Let us know if the calculator confuses you or the answer you get seems off by quite a bit from what you think it should be.

But most of us aren't math geniuses and we rely heavily on specialized calculators to get the answers for us. Not that you have to be a genius to figure it by hand. Just that you have to have the memory of a genius to be able to remember the formula's without having to look them up.

#### ScrewyBrewer

##### ezRecipe - The Easy Way To Awesome Beer!
HBT Supporter
I am about to brew my first batch just using my 10 gallon Spike kettles. I have always used coolers for my HLT and mash but I now have a brew stand.

Can anyone help with how much I have to heat 6.7 gallons of water in HLT so when I add my grains, 15 pounds, to the mash tun the temp drops to around 150 degrees?

=D4+0.192*(D4-C4)/B4+E4

=(((D4*9/5)+32+0.192*((D4*9/5+32)-(C4*9/5+32))/(B4/2.0863511218233)+(E4*9/5)+32)-32)*5/9

When entered into a spreadsheet, here is something that will help you, but you must also enter the grain temperature and mash thickness. Change the degrees of heat loss introduced by hoses and vessels that most closely match your brewing setup.

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#### day_trippr

##### Structural Duct Tape Applications Engineer
A big chunk of calculating strike water temperature is in the equipment, and that varies brewer to brewer. There needs to be something thermal-mass-based in the math to account for that.

Where did that "Heat Loss Factor" come from?

Cheers!

OP
OP
R

Thanks guys!

#### ScrewyBrewer

##### ezRecipe - The Easy Way To Awesome Beer!
HBT Supporter
A big chunk of calculating strike water temperature is in the equipment, and that varies brewer to brewer. There needs to be something thermal-mass-based in the math to account for that.

Where did that "Heat Loss Factor" come from?

Cheers!
The heat loss factor is the degrees of heat loss introduced by hoses and vessels that closely match your brewing setup.

#### day_trippr

##### Structural Duct Tape Applications Engineer
Ok, but how is that number generated by the user for his/her equipment?

Blessedly, Beersmith makes strike water temperature calculations easy - but its accuracy is significantly dependent on an "equipment profile" that incorporates heat sink (mass) and radiation loss (surface area) factors. I was particularly lucky using a well established standard (principally, a 20 gallon Boilermaker G1 kettle with their false bottom) that others had done the work for so I didn't have to go through the experimentation to generate those thermal factors myself...

Cheers!

#### ScrewyBrewer

##### ezRecipe - The Easy Way To Awesome Beer!
HBT Supporter
Ok, but how is that number generated by the user for his/her equipment?

Blessedly, Beersmith makes strike water temperature calculations easy - but its accuracy is significantly dependent on an "equipment profile" that incorporates heat sink (mass) and radiation loss (surface area) factors. I was particularly lucky using a well established standard (principally, a 20 gallon Boilermaker G1 kettle with their false bottom) that others had done the work for so I didn't have to go through the experimentation to generate those thermal factors myself...

Cheers!
Initially, just set the heat loss temperature to 2 degrees. After dough-in, note the temperature of your mash. Next time adjust the heat loss temperature up or down as needed. As you mentioned, heat loss will vary somewhat with every brewing system and brewer.

#### kevin58

##### Supporting Member
HBT Supporter
Also factor in the temperature of your grain at the time of dough in. I'm doing a brew right now and I always stick my thermapen in the grains before setting my strike temp.

#### day_trippr

##### Structural Duct Tape Applications Engineer
Grain temperature is clearly covered above - and is comparatively simple to calculate its effect.
Brew rigs are harder...

Cheers!

#### pvtpublic

##### Whale Oil Beef Hooked
Initially, just set the heat loss temperature to 2 degrees. After dough-in, note the temperature of your mash. Next time adjust the heat loss temperature up or down as needed. As you mentioned, heat loss will vary somewhat with every brewing system and brewer.
Yes! Taking notes is imperative in knowing how to adjusting this. That's how I found out that I need to add 2 degrees to the temp that this calculator puts out for my set up.