Date: Wed, 29 Dec 2004 11:02:37 -0700
Reply-To: Karl Wolz <wolzphoto@WORLDNET.ATT.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Karl Wolz <wolzphoto@WORLDNET.ATT.NET>
Subject: Re: LP gas question--does this happen to you?
In-Reply-To: <004801c4edc1$e319b3c0$0100a8c0@OnWord>
Content-Type: text/plain; charset="us-ascii"
David,
Different substances vaporize at different temperatures; water at 212F -
butane at around 33F, IIRC, and propane at somewhere around -44F.
In doing some research to better answer this question, I actually
learned something!
When you purchase LPG, which we normally think of as simply propane, you
are buying a combination of propane and butane, which have similar
characteristics - the biggest difference being the vaporization points.
It seems that if you purchase your LPG in the summertime or in the
south, you are likely to get a higher percentage of butane, and
consequently a fuel which will not vaporize in low temperatures (MN?).
By using your stove and simply moving about, you warmed the van enough
to vaporize the LPG in your stove. Once started, it provided enough
heat to itself that it kept on cookin'.
Below is the source for the information above.
Karl Wolz
"Why are Butane and Propane used in combination?
While butane and propane are different chemical compounds, their
properties are similar enough to be useful in mixtures. Butane and
Propane are both saturated hydrocarbons. They do not react with other.
Butane is less volatile and boils at 0.6 deg C. Propane is more volatile
and boils at - 42 deg C. Both products are liquids at atmospheric
pressure when cooled to temperatures lower than their boiling points.
Vaporization is rapid at temperatures above the boiling points. The
calorific (heat) values of both are almost equal. Both are thus mixed
together to attain the vapor pressure that is required by the end user
and depending on the ambient conditions. If the ambient temperature is
very low propane is preferred to achieve higher vapor pressure at the
given temperature."
You can learn more at: http://www.e-lpg.com/lp_gas.asp
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On
Behalf Of
> David Devere
> Sent: Wednesday, December 29, 2004 9:17 AM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Re: LP gas question--does this happen to you?
>
> I love all these cold weather questions. It means I have
something to
> contribute : ). The propane won't light in extreme cold. I don't
> understand the physics but I experienced it last year when winter
camping.
> The low was around -7F and that morning the stove refused to light. I
tried
> everything. Eventfully I used my whisper light camp stove to make
coffee
> and I placed it on the top of the westy stove after removing the stove
> grill. The heat from the camp stove must have warmed the piping in
the
> westy stove because after the coffee was made I was able the light the
stove
> top and make a warm breakfast. I don't know why but it worked. I'm
sure
> glad I travel with a backpacking stove.
> So in answer to your question: everything is fine with your propane
> system it's just cold.
>
> Cheers-
> Dave
> Two Harbors MN
>
>
> ----- Original Message -----
> From: "Jim Felder" <felder@KNOLOGY.NET>
> To: <vanagon@GERRY.VANAGON.COM>
> Sent: Wednesday, December 29, 2004 8:38 AM
> Subject: LP gas question--does this happen to you?
>
>
> > A few days ago when it got down to the teens around here, I almost
> > couldn't get the stove in my Westy lit;. I never got the gas heater
> > going from the piezo starter, either, but then I didn't try very
hard.
> >
> > There just didn't seem to be enough gas/pressure to support anything
> > but a pilot flame.
> >
> > When the weather got into the 40s I tried it again and everything
> > worked fine.
> >
> > I was wondering if this was common because I recently had the tank
> > filled, and if it's not a common phenomenon I need to chase down the
> > leak or regulator problem.
> >
> > Any ideas?
> >
> > Jim
|