Cold crash suck-back volume estimate?

[jerrylotto]

You will still have suck-back, as the negative pressure is caused by the colder liquid absorbing more gasses, not just CO2. You also have the volume of the liquid itself shrinking due to the temperature change.

Water volume change by temperature is pretty negligible, the bigger change is the volume of gas overhead shrinking (decreasing pressure). You can use the ideal gas law PV=nRT as an approximation - pressure in the headspace is approximately proportional to temp (in degrees Kelvin)- dissolving C02 reduces "n". Water shrinks slightly with decreasing temp above 4 degrees C and then expands again as temp drops below 4C until it after it freezes with decreasing temperature. Best way to cold crash IMHO is under positive CO2 pressure in a keg.