Date: Fri, 2 Nov 2001 08:30:45 -0600
Reply-To: Chris Stann <ChrisS@INFORMS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Chris Stann <ChrisS@INFORMS.COM>
Subject: was Propane pressure facts - now staying warm
In-Reply-To: <F803SOlbpH71yEXUIEA000190ed@hotmail.com>
Content-Type: multipart/alternative;
http://www.coleman.com/coleman/ColemanCom/prod_Detail.asp?Product_id=5053-75
1&CategoryID=3000&SourcePage=PROD_LIST.ASP&SubmittingPage=Prod_subcategory.a
sp
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I use a Coleman Power cat. It has a built-in fan to circulate the air. I
camped in a temp of 25 degrees and, with the top down, it was too hot
inside. The fan spread the heat throughout the van, and I had the the side
windows and the skylight open about 1 inch. This circulating action also
prevented any 'settling' of deadly gasses folks talked about here.
I am sure you camp in much colder weather, but the fan really helps to
spread the heat.
Chris.
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com]On Behalf Of
Randy Charrette
Sent: Thursday, November 01, 2001 8:50 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: Propane pressure facts
I guess I started this thread and the truth is I am not happy at all with
the performance of my coleman black cat. I go Skiing and ice climbing in the
winter and arrive at my destinations very late at night. This heater can not
keep up for the cold that I encounter. However it was affordable,and I had
read good things about it. I would gladly pay a couple of hundred dollars
for a good ventilated system that would fit in a vanagon. Looking on RV
sites I have not found a system under $400, and even at that they are to big
to fit reasonably behind the front passenger seat and still have room(I have
2 dogs and a wife that crash in there too.). So anyone that has found a good
system PLEASE let me know. I am willing to install a propane tank and/ or
aux. battery (plan too anyways). Thank for the propane education!
Randy Charrette
87' Syncro weekender
Longmont, CO
>From: Dennis Haynes
>Reply-To: Dennis Haynes
>To: vanagon@GERRY.VANAGON.COM
>Subject: Propane pressure facts
>Date: Thu, 1 Nov 2001 20:54:47 -0500
>
>There has been a lot of talk about the use of propane heaters these past
>few days so I though I would clear the air!
>
>The pressure in the propane tank is a function of the propane and
>temperature. As long as there is liquid in the tank, the pressure will
>be close to that stated in the chart.
>http://www.gasplants.com/property.htm A bulk tank and portable cylinder
>will have the same pressure at the same temperature. Note that propane
>and butane are great for carrying in small containers because they
>compress to a liquid easily. The latent heat of vaporization explains
>why a propane tank gets cold as the gas is being used. Yes, heat has to
>be absorbed in order to create the vapor you burn to make heat. Yes the
>relatively low pressure needed to compress to a liquid also makes it
>possible to use as a refrigerant.
>
>Most propane appliances need the vapor pressure reduced to 11" water
>column pressure. This is the job of the regulator. Appliances designed
>to work with portable cylinders rely on an orifice to limit the flow,
>thus reducing the pressure during use to a level appropriate for the
>device. The major advantage of propane as compared to other fuels is
>it's extremely wide flammability range. Air fuel mixture is not critical
>for a clean burn. The down side here is that any propane out of control,
>(a leak), presents a real hazard since the vapor is easy to ignite and
>reducing the oxygen supply will not extinguish it. You would never see
>an electric pump placed inside a propane tank like we frequently see in
>gasoline tank. Yes. The pump in the gas tank relies on the fact that
>there is little oxygen so there is little chance of ignition. Another
>problem with a propane fire is the fact that the tank is already under
>pressure. As the tank is heated in a fire, the vapor pressure will rise
>rapidly, especially as the propane tries to boil. This can cause a
>BLEVE, (Boiling Liquid Expanding Vapor Explosion).
>
>Using a non vented heater in a Vanagon is not very smart. I did this
>many years ago and now consider myself lucky. These heaters need proper
>ventilation to ensure a safe oxygen supply for you and to ensure no CO2
>accumulates. I believe the recommendation is two 12" X 12" openings for
>each 5,000 Btu. One opening high, one low. Not much is going to remain.
>Remember, most of these things are designed for tents. If you must use
>these, get a good propane alarm and CO2 alarm and mount according to the
>directions. You should also make sure the heater has low oxygen cut off.
>Do not rely on the battery operated units. Go to an RV supply and get
>the permanently installed 12 volt models.
>
>All combustion produces water vapor as a by product. In the winter this
>will accumulate behind the interior panels of the van and never dry out.
>It will even get inside the square tubes in the sides and roof of the
>vans. My 1970 van rusted in places I never though possible in only 2
>years of occasional camping this way.
>
>If you really need to add heat your van, you should go with a
>permanently installed, vented heater. Do it right. It is your life at
>stake here. As for connecting the portable heaters to a bulk cylinder, a
>good RV supply can get you the needed fittings and adapters. Marshall
>Brass makes a great T that goes between the tank valve and the
>regulator. (Extend a Stay).
>
>Last spring, I posted a line of portable heaters that stayed outside and
>used a 3" hose to pipe in the heat. I forgot what brand they were. I'll
>look some more and repost when I find it.
>
>Hope some of this helpful. Remember, be very careful suing propane and
>these portable heaters. It only takes one mistake or unknown situation
>to make a disaster.
>
>Dennis
>
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