thehopbandit
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I don't actually have any Co2 equipment in front of me, but I am wondering more about the science/specifics behind the process. I realize I'm probably digging way too deep into the subject, but it is interesting for me and I'd like to get the scientific understanding behind it. Please excuse my ignorance if I describe something that doesn't make sense or if I am way off base.
I understand that when you move the Co2 tank from room temp to a colder temp say, inside the fridge, the pressure reading on the tank will decrease due to the colder temperature making the Co2 more dense. The Co2 in the tank is the same.
1. How does temperature affect the Co2 regulator controlling how much gas goes to the keg? I'm not talking about the gauge on the Co2 tank that tells you how much gas is left, but more the regulator that is controlling the PSI on the keg. Does the mechanical operation of the regulator keep output PSI constant regardless of temperature? For instance, if you had a keg at 12 PSI and dropped the temperature of your equipment, would that regulator continue to output 12 PSI or would the output PSI drop without adjustment from the user?
I understand that pressure is pressure. So, I am not sure if I am scientifically describing this correctly, but wouldn't you actually be transferring more Co2 molecules at 12 PSI at 32F than at 12 PSI at 50F, ignoring the solubility of the liquid and considering just the amount of transfer through the line.
An analogy would be a balloon filled with gas. When you drop the temp, the balloon shrinks and the pressure inside the balloon goes down. However, the amount of gas in that balloon stays the same, even though the volume and PSI decreased. Say the PSI on that ballon was 5 PSI. You decrease the temp, it shrinks in volume and the pressure goes down.
2. If you wanted to keep the pressure constant at 5 PSI, wouldn't you technically need more gas in the balloon to keep that PSI at that lower temperature?
3. In this regard, does keeping output PSI constant as temperature changes actually affect the physical amount of Co2 being delivered to the beer? As with the example above, if you are delivering 15 PSI to the beer at 32F and 15PSI to the beer at 50F, wouldn't there be more Co2 molecules transferred to the keg at the lower temp, even though pressure was constant?
I also understand that there are two main things that affect how much Co2 gets into the kegged beer. The first being the PSI of the Co2 and the lower the temp (to an extent) of the beer, the greater the solubility of a gas into the liquid.
4. How does the temperature of the liquid (beer/keg) work in conjunction with the temperature of the gas to determine how many volumes of Co2 you end up with in the beer. I understand the Co2 volume charts on the net, but it seems to me they only take into the account the solubility and temp of the beer, not the temperature of the gas, if my above thinking is somewhat correct.
Thank you for reading, and let me know if I can clarify anything.
I understand that when you move the Co2 tank from room temp to a colder temp say, inside the fridge, the pressure reading on the tank will decrease due to the colder temperature making the Co2 more dense. The Co2 in the tank is the same.
1. How does temperature affect the Co2 regulator controlling how much gas goes to the keg? I'm not talking about the gauge on the Co2 tank that tells you how much gas is left, but more the regulator that is controlling the PSI on the keg. Does the mechanical operation of the regulator keep output PSI constant regardless of temperature? For instance, if you had a keg at 12 PSI and dropped the temperature of your equipment, would that regulator continue to output 12 PSI or would the output PSI drop without adjustment from the user?
I understand that pressure is pressure. So, I am not sure if I am scientifically describing this correctly, but wouldn't you actually be transferring more Co2 molecules at 12 PSI at 32F than at 12 PSI at 50F, ignoring the solubility of the liquid and considering just the amount of transfer through the line.
An analogy would be a balloon filled with gas. When you drop the temp, the balloon shrinks and the pressure inside the balloon goes down. However, the amount of gas in that balloon stays the same, even though the volume and PSI decreased. Say the PSI on that ballon was 5 PSI. You decrease the temp, it shrinks in volume and the pressure goes down.
2. If you wanted to keep the pressure constant at 5 PSI, wouldn't you technically need more gas in the balloon to keep that PSI at that lower temperature?
3. In this regard, does keeping output PSI constant as temperature changes actually affect the physical amount of Co2 being delivered to the beer? As with the example above, if you are delivering 15 PSI to the beer at 32F and 15PSI to the beer at 50F, wouldn't there be more Co2 molecules transferred to the keg at the lower temp, even though pressure was constant?
I also understand that there are two main things that affect how much Co2 gets into the kegged beer. The first being the PSI of the Co2 and the lower the temp (to an extent) of the beer, the greater the solubility of a gas into the liquid.
4. How does the temperature of the liquid (beer/keg) work in conjunction with the temperature of the gas to determine how many volumes of Co2 you end up with in the beer. I understand the Co2 volume charts on the net, but it seems to me they only take into the account the solubility and temp of the beer, not the temperature of the gas, if my above thinking is somewhat correct.
Thank you for reading, and let me know if I can clarify anything.