Co2 Pressure Towards End Of Cylinder

[coolie]

Just a very simple question really; The gauge on my CO2 was around 70 for ages, checked back a couple of months later and it was 50. A couple of months later before I checked it again, (thinking it would be about 40)  and it is completely empty on zero and the bottle is empty and the gas must have stopped the same day by coincidence. Do you find it goes suddenly like that. I though I would have at least weeks of the pressure weakening and having to adjust the regulator, but no. Is this normal?

 

[Lunar Jetman]

Yep, that's pretty much how its been with my cylinders. The pressure holds for ages and then drops away very quickly.

 

[DrRob]

Yes, it's normal, the cylinder holds CO2 in liquid form, this, under pressure, stays put and slowly evaporates as the cylinder empties.
 
Eventually you reach a point where the liquid is pretty much depleted and there's not enough to evaporate to keep the pressure up, at this point the gauge starts to drop, but you're already almost out of CO2.
 
In a nutshell, if the pressure starts to drop, then you're almost out and you need to get a new cylinder sorted.

 

[coolie]

Great - thanks for the replies. Awful timing as most places now closed for xmas hey?

 

[KirkyArcher]

Is even the same with compressed air cylinders, there is a rapid drop off in pressure as the tank nears empty.