Should I chill my CO2 Bottle first?

The only two places by I found to fill my CO2 bottle both seemed to indicate that they wouldn't need to chill my bottle first before filling. So I was thinking of just putting it in my freezer before I go and then putting it in a cooler while I drive with some ice packs.
Good yes? Needed?

 

What is the theory behind chilling the bottle?
Co2 is filled by liquid weight. Temp has no affect.

 

I ready very strong opinions both ways on the subject. Having never had a CO2 bottle I can't ascribe to either method being better, but if one has the chance of being better then maybe its safer to try that?

 

Usually the places just do an exchange rather than a fill, are you certain you're even going to be getting your own tank back?

 

Yes, I specified it was a refill. Also its at a paintball place, so they wouldn't have 5# tanks anyways. Its the only place that will do it for me while I wait in the evening. Everywhere else wants me to drop it off and pickup later OR they all leave at 3 or 4pm and I don't get off work that early. The painball place owners live 2 min away from their shop and the lady said if i called they would just come over and do it even if its just after 5pm. the only issue was that its a $20 refill. Airgas is about 25min away, they leave a 4pm, and it would be $14

 

I could be wrong, but I think it kinda depends on the fill station...

I used to work in a sporting goods store that filled paintball CO2 tanks. The only way to get the customers tank to hold "x" ounces of CO2 (generally 9oz or 20 oz) was to partially fill the tank, then purge the whole thing. This would bring the tank itself down in temp pretty substantially. Once the tank itself was good and cold, you could actually pump the proper amount of liquid CO2 into it.

I could be wrong here, but if I remember my chemistry correctly, there's basically 2 ways you can keep CO2 liquid under normal circumstances... 1) cool it down, or 2) keep it under pressure. The problem with a "warm" tank is, when the liquid CO2 gets pumped into it, it tends to turn to gaseous CO2 because the tank is warm, and not (yet) under enough pressure to keep the CO2 liquid.

 

Filling a CO2 bottle generates heat, which limits the amount of liquid CO2 a bottle will accept before pressure equilibrium is reached between the source and destination bottles.

If you don't have an assist pump, you need to chill the bottle. Otherwise, you'll only get a partial fill.

There are two easy methods for chilling an empty bottle:

1. Stick it in the freezer for an hour or so.
2. Push a few ounces of liquid CO2 in an empty bottle and rapidly release it.

 

I've got a fill station. I've never been able to get a full charge into a bottle without chilling it (either in the freezer, or by partially filling and then emptying it for a quick phase-change chill).

I'd be very very leery about getting my bottle filled anywhere that doesn't do this - it almost guarantees that you're not getting a full fill. If they're not filling by weight and using a scale to measure - run away! An partial fill might be a rip-off, but an overfill is downright dangerous.

 

Good to know. I am having a very hard time finding a place that will do a refill that is close by OR is open later than 5 OR is open on saturday. I am getting my kit today and I want to play with it TODAY!!! or tomorrow when the beer has had a chance to chill before i hook it up to CO2.
I really don't want to exchange my brand new aluminum CO2 bottle for a crappy steel one.

 

hmm. I've always just taken my bottle from my keezer and had it filled. Also played paintball for year and never heard any mention of this.

That being said, last time I got my bottle filled, I took it home and I was WAY under weight. only 2lb over Tare. I it back and they refilled it full that time.

Learn something everyday I suppose.

 

Did the store have a fill station with an assist pump? Something like this? They're pretty loud since it's pneumatic powered.

 

i dont think you need to chill it... c02 is freakin cold when released anyways...ever seen the bottles frost up when co2 gets let outta the tank? thats my reasoning