pressure drop during carbonation

[rouge_brewer]

Im keeping for the first time, checked all connections for leaks with soapy water and tightened to eliminate any bubbles. My soda has been in there for two days so it's not carbed yet.

If I set my regulator to 40psi then shutoff the supply from main tank should I expect a psi drop as the liquid absorbs the co2? Or is any drop in pressure a sign of a gas leak.

 

[bigbeergeek]

The gas pressure in the headspace will equalize with the gas pressure in the soda, so your pressure in the headspace will drop, unless the soda is fully carbonated.

 

[rouge_brewer]

Anyone seen a formula for calculating this or have a rule of thumb for how much you would expect it to drop?

I refurbished old kegs; while I think their good now I don't really know due to the carbonation drop. For instance, over 10 hrs it went from 40 to roughly 25 psi.

I suppose Ill shut off the supply at the manifold next to eliminate that section.

 

[rouge_brewer]

Confirmed no pressure drop between regulator and main co2 tank. So topped up with 40psi then shut tank off... 12 hrs later hardly any drop. Must be getting close to equilibrium but its not that carbonated yet.

3 more kegs to refurbish and test.

 

[jddevinn]

Rouge,

The CO2 takes time to get absorbed into the liquid. As the CO2 that is in the head space is being dissolved into the beer --- **** soda ---- the pressure will drop if the CO2 tank is not connected to replenish. When the beer reaches the carbonation level you are targeting it will stop dissolving. At that point you could remove the tank and the pressure will stay stable until you dispense. A CO2 pressure temp table is here

40psi could be VERY carbonated depending on the temperature, I don't know about soda but you may want to check this.

Carbing normally takes several days to a week or so depending on several things. Carb time is mostly dependent on surface area of liquid in contact with the gas...... so shaking the **** out of the keg will increase transfer a BUNCH. 10-15 minutes of shaking should get you fully carbonated.