Sight gauge calibration

For those who’ve calibrated their own HLT sight gauge, what water temp did you calibrate at? I’m thinking ~165F.

I used room temp water :shock: but the levels came out pretty darn close.
I chalked up any slight difference in measurements to something I did wrong (like apparently use room temp water) …

I would calibrate it at your tap water temperature, that way you’ll have accurate volumes when you’re filling the HLT. The volume is only going to increase by ~2% or so between 70 and 160.

http://physics.info/expansion/water-1.html

[quote=“Glug Master”]I would calibrate it at your tap water temperature, that way you’ll have accurate volumes when you’re filling the HLT. The volume is only going to increase by ~2% or so between 70 and 160.

+1 I heat my sparge water to 190, and haven’t noticed a significant rise in the sight glass.

[quote=“Glug Master”]I would calibrate it at your tap water temperature, that way you’ll have accurate volumes when you’re filling the HLT. The volume is only going to increase by ~2% or so between 70 and 160.

+1 Thermal expansion of water is a non-issue. Misreading your sight-glass is probably a bigger source of error.

https://en.wikipedia.org/wiki/Meniscus

Should have run the numbers before I asked the question.

The change in the units volume when temperature change can be expressed as
dV = V0 β (t1 - t0)
where
dV = V1 - V0 = change in volume
β = volumetric temperature expansion coefficient (water=0.000214)
t1 = final temperature (oC)
t0 = initial temperature (oC)

For my 50 gal HLT going from 11C to 70C the dV =0.6527 gal. I’m going to relax and not worry about the 2/3 of a gallon.

[quote=“fightdman”]my 50 gal HLT[/quote] :shock: Wow, how big of batches do you brew?

75 gal kettle allows up to 2bbl batches (if I’m careful)