Mash tun heat loss - calibration

[shunt]

I did a test of my mash tun today. It's 50F outdoors, and after 65 minutes in the tun, my water went from 156 to 123.
Is this something that I should be worried about? This was only water and it was only a gallon in a 10 gallon cooler. Nothing scientific here but still...

[Crut]

i wouldnt base anything off of that small amount of water. Pay attention and take notes next time you brew. The thermal mass of crushed barley and water wont cool down as fast as just a gallon of water with 9 gallons of deadspace. Also, maybe try preheating with a gallon or two of HOT water before mashing.
my $.01 worth-Crut

[UhrigBrauer]

Definitely preheat your mashtun, this takes out the pain in finding your thermal mass for your tun.... this essentially sets it to zero. Also, make sure your grain is stored indoors where it can be kept at a nice room temp so that it doesn't bring down your temps. Other than those points, I try to keep my "tun in the sun" to help with cold temps.

Don't worry though, put some beer in there and start mashing!

JU

[shunt]

good points.

Thanks for the feedback.

[slanted & enchanted]

i use a converted keg and i find heat loss over an hour with a relatively full tun is minimal. usually a degree or two, and that's with probably a 45 degree air temp (my brewery is in a detached block garage, so it gets pretty cold in there even with a kerosene heater). i'd suspect a full cooler would hold heat better than the thin stainless of my keg.