Heat Loss in BeerSmith with crazy insulated MashTun?

[hammy48]

I have never brewed before and this saturday is going to be my first beer. Beer Smith wants to know my "Mash Tun Specific Heat" in the units of "cal/gram-deg c". It guessed at a number of ".15" for my system (3 stainless kegs) but my system is a little different because...

I have an insulated box around my MT. I have 4 inches of hard insulation foam board in all directions contained in a plywood box around my MT.

Any guesses as to what I should enter in as a value for my first brew?

After this brew I can just get close based on what I perceive the heat loss to be from my thermometer.

Thanks!

 

[danielbt]

"Mash Tun Specific Heat" is not related to how fast your rig loses heat, it's about how much heat the material of your mash tun absorbs before reaching equilibrium. If the interior of your mash tun is steel, then .12 is what you want to use.

You'll input the temp of your mash tun itself in your mash profile.

 

[hammy48]

So to compensate for my well insulated MT I just want to lower my infusion temp?

Thanks for the reply. That makes sense... although I did notice you said .12 and Beer Smith uses .15 as their default for a steel keg.

EDIT: Beer Smith won't let me edit the infusion temp... although it will automatically adjust it if I change the dead space factor. Maybe This is also not related to how well my MT is insulated...

 

[danielbt]

The setting for steel in BeerSmith 2 is .12. Are you using the first version of BeerSmith?

In BS2, you can make mash profiles where you specify the starting temp of the mash tun, and it uses the "Mash Tun Specific Heat" in its calculation for strike water temp. No reason to lower the temp, just use the ambient temp the tun has been sitting in.

To be specific, there is no need at all to adjust temperature because you have a well insulated tun. You can just be confident that that temp you mash at will be held for the entire mash period.

 

[hammy48]

I see. Thanks for the info. Now I just need to measure my MT dead space (becausey MT drains out the bottom so I have much less dead space than the automatic setting).

Yes I am using BS2, but set it to 10 gallon steel kegs not the pot setting which gave me .12

Thanks again!