Should I calibrate to ice water or boiling water?

[beertastic]

I found the boiling point of my area to be 210.69F according to this calculator:
http://www.thermoworks.com/software/bpcalc.html

The thermometer read 210.7F (spot on).

But in ice water, it is reading 33.2F (a good deal off)

I'm most concerned with mash temperatures. Should I calibrate to match the ice water, or leave it alone?

 

[CastleHollow]

I'd have to say leave it alone, although to be honest, that's a level of precision I have never even worried about.

 

[neo71665]

Done correctly you calibrate to both. Boil then adjust, freeze then adjust, and repeat until there is no adjustment between the two.

Now do you need it accurate to .0007 degree is up to you. Personally I don't go that far and still enjoy my brew.

 

[Wynne-R]

Did you do a proper ice bath?
http://www.thermoworks.com/blog/2010/10/making-a-proper-ice-bath/

Very often, people don’t stir or use enough ice.

If your measurements are correct, I’d stick with what you have. Mash temps are way closer to boiling than freezing.

 

[beertastic]

Did you do a proper ice bath?
http://www.thermoworks.com/blog/2010/10/making-a-proper-ice-bath/

Very often, people don’t stir or use enough ice.

If your measurements are correct, I’d stick with what you have. Mash temps are way closer to boiling than freezing.

Thanks, I wasn't using quite that much ice, but I'm still getting the same reading.

I measured my STC-1000, and it's off by the same amount (0.7C), so I don't know what to think.