Beer Forum

Okay I probably know the answer to this but just checking. I just had a 10 lb tank filled and noticed the gage was over 1200 when I hooked it up inside the fridge last night. This AM the reading is down to 500. I assume this is because of the temperature drop and not due to a leak.

yeah it should be fine thats about where mine sit at

When the bottle contains liquid the gauge reads the vapor pressure of CO2 which depends only on temperature - not on the amount of CO2 present. The reading of 500 psig says the temperature in your refrigerator is 29 °F. Actually what it really says is that your gauge is off a bit because I doubt you keep your fridge that cold. At 45 °F the vapor pressure of CO2 is 621 psig.

If the pressure reads over 1087 psig (e.g. your reading of 1200) that means the temperature of the bottle is above 88 °F and there is no liquid in the bottle. The stuff in there isn't a gas either but rather a supercritical gas. The pressure still depends on temperature but also on the amount of CO2 in the bottle. Again, I suspect that the gauge is reading off a bit as I doubt it is over 88 °F in your house.

Thanks so much for the replies- I knew someone could give me the skinny on this. I just wanted to confirm that my system wasn't leaking as it is expensive when I get my tank refilled as its brand new aluminum and I don't switch out.

The information you were given by aj correct 500psi is close enough with gauge inaccuracies to not worry about it. If your are posting more then $25 for a fill you need to find a new vendor or have a conversation with the guy at the counter as I only charge $25 for a twenty pound refill.