They're full of air to start.  That's too lean to burn.  In use they're
full of propane which is too rich to burn.  You have to get a new tank past
the point of containing an explosive mixture before you can use it or the
first time you light something it could flash back through the lines and
blow the tank apart.

Yrs,
d

On Wed, Mar 22, 2017 at 6:36 AM, Roman Haag <romanhaag@ymail.com> wrote:

> So a new tank needs to be purged?  I did not know this.
>
> Sent from someone's plumbing
>
>
> > On Mar 22, 2017, at 01:37, David Beierl <dbeierl@ATTGLOBAL.NET> wrote:
> >
> > Off the cuff -- I'd take it to any propane place to purge.  During
> purging
> > at some point there will be an explosive mixture in the tank, you don't
> > want to be around if it finds a spark.
> >
> > Yrs,
> > d
> >
> >> On Tue, Mar 21, 2017 at 9:32 PM, gary hradek <hradek@yahoo.com> wrote:
> >>
> >>
> >> I just bought a Worthington Pro Grade 4.25 lb. Empty Propane Tank from
> >> Home Depot to use with my Colemanstove.   The 1 pound cylinders are
> >> nowclose to 8 dollars a piece.   I was goingto fill it from the 20 pound
> >> tank but they say something about purging it.   Can I just fill and
> empty
> >> it a few timeswith propane vapor before trying to fill it with the
> liquid
> >> by inverting the 20pound tank?   I am guessing there is acharge to have
> it
> >> purged somewhere?
> >>
> >> Gary
> >>
> >>
>