It's really keeping warm in bed that we're after, right?

  Why not consider using those 12V electric blankets under sleeping bags, and have a couple of gel-cell batteries to power them, in addition to the Black-cat for "room" warmth?

  I think you'd get more comfort with this method, than you'd get with heavy-duty propane combustion.

  Marshall Ruskin, 84 Westy
  Aloha from Winnipeg!

  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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