Date:         Tue, 7 Aug 2007 21:35:17 -0600
Reply-To:     David Johnson <davidj@ELPASOTEL.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         David Johnson <davidj@ELPASOTEL.NET>
Subject:      Propane Gauge for Westy - The Final Word?  Probably not.  hehe.
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Ok - thanks for all the responses so quickly.  Based on a few notes,
I did some more global research into propane tanks in general, and
the way gauges work.  Here is what I found out.

Small tanks like a BBQ tank have three options.  One is the magnetic
strip that sticks to the side, and basically registers changes in
temperature.  The changes in temperature are quite small, but enough
that the thermosensitive ink or marker is able to give a general idea
of what is left.  A pressure gauge does exist for BBQ tanks and for
RVs, however as a couple astute members pointed out, and as even
pointed out by the website of the company that makes it, the gauge
really only gives you an emergency warning when the gas is almost
completely gone.  According to the web site, you only have about
10-15 minutes of gas left once the tank gets into the red zone.
Granted, there is a yellow area on the gauge that is supposed to tell
you when you are having the "warning signs" of running out of gas,
but it is pretty small, and my guess is you would go from yellow to
red to out in about 20 minutes.  There is also a scale based gauge -
weigh the tank, and when it gets below this weight, you need gas.

For very large tanks like the one I have sitting out back of my
house, apparently they use a float on the gauge of some sort, almost
like a gasoline tank would.  I did not find out a whole lot about
this, but that would explain why the gauges on all the propane tanks
I have seen only go down to about 10% - that is about 50 gallons in a
500 gallon tank, and I would guess the float is simply not accurate
much past that point.

So, where does that leave us?  There is no room in a little Westy
sized tank for a float system, or at least not that I have found.
Perhaps a very small float could be devised, but I doubt the market
is that great for it.  The stick on systems won't work because A) our
tank is not vertical, so the temperature change would be hard to
track and B) one of the list members mentioned our tank walls are a
lot thicker than a BBQ tank.  Can't verify that, but might be true.
And of course, a weight based system doesn't work on a permanently
mounted tank.  While it is quite easy and relatively cheap to put on
a pressure based gauge, I really think the true effectiveness of such
a system is pretty minimal.  The last thing anyone wants to do is
find out after getting set up camping that, "oops, only got 15
minutes of cook time left."  But if anyone wants to read more about
that system, it is at www.flameking.com.

So, while the short answer to the question was - "You cant put a
gauge on that tank," the longer answer is that the above are the
reasons why.

Thank you, Colorado, and good night!

David.

PS - random thought - didn't late model Vanagon Westies and all
Eurovan poptops have a 3rd LED indicator for propane level?  I know
the Rialta based on a Eurovan chasis had one.  So how did that work?