Emptying a Bottle

Teg Veece

I haven't been SCUBA diving for 2 years now and I've just taken my gear out of storage. I noticed that my bottle is filled with 220 bar of compressed air. I heard that the air goes bad after 6 months so I need to empty it. I'm just wondering what's the best way of going about this?
I don't want to just open the valve fully because in case condensation forms on the inside. Should i just leave the valve marginally open over night or is this something i need to go to the dive store about?

Benny-c

I'm not sure about the bad air after 2 years, but the bottles are more than likely due a VIP (every 2.5yrs) ,or even a hydro (every 4 years AFAIK) so check the stamps on the bottles and bring them to wherever does this in your area and let them bleed the bottles.

Scuba.ie

If you haven't used the tank(s) in two years then they will probably be due a VIP (every 2.5 years) or possibly a Hydro (every 5 years). The inspector will empty the bottle as part of the test, and if there is any condensation (now presumably rust) they should be able to sand blast it for you.

dave_r

I would have the bottle re-tested even if it is still in test. Storing a bottle with 220 bar is not a good idea (however the bottle should not be empty either). The more air in your tank, the more corrosion is possible when moisture is present. Also extremes of temperature may have caused the bottle to go beyond it's working pressure from time to time. If the bottle was stored on it's side then the corrosion will have happened at the weakest point (the sides).

If corrosion has happened the oxygen that created the rust will have come from the air inside, so I would say that there is a risk of hypoxia if you use the two year old fill.

seadeuce

To answer your question, wrap a towel around the pillar valve before you open it. That way the condensation will soak into the towel and not form around the pillar valve itself.
Bleed it slowly, opening it more at intervals. It should take you 25/30 minutes to empty.


Seadeuce