I am going to do a one night camp at Surly Darkness tomorrow night and have
been experimenting with ways to add some extra heat independent of my propane
catalytic unit.

I am doing a couple of things, both are quite simple.

First, preheat the interior as much as possible.  I am using a 1200 watt
electric heater running at 500 watts (low).  My current outside temperature is
39F, and my van has been at 75F for over 24 hours.  There is a lot of heat
stored in the interior, especially the 150 lbs of the battery bank.

Second, to heat things up quickly (when the interior was at 37F yesterday), I
bought 2 4.5 gallon water containers from Fleet Farm.  They actually hold 5.5
gallons or 46 lbs of water.  My hot water temperature at home is 148F.  If you
do some simple math where 1 lb of water heated 1 degree F, or cooled, is 1 BTU.
 I am assuming the low temperature cutoff is 80F.  So (148-80) * 46 is 3128
BTUs.  I have 2 of those containers.  That is more than 2 hours of my propane
3000 BTU heater.  I am using those during the preheat stage and will refill
them for the camping stage.

I also plan to fill the tank in the van with the same temperature water and
leave the top cover open.  I think that's another 11 gallons, so would add
2*3128 or 6256 BTUs.  Between that, the van 24 hour preheat, my body heat,
waste heat from the fridge, and the heater, I expect I will be very snug
tomorrow night at Darkness Day Eve.  Overnight temperatures are expected to be
around freezing depending on cloud cover.

I hope someone else from the list will be there.  We see people from all over
the continent.  Good beer, good people.

tom

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Tom Ring K0TAR EN34hx

Never attribute to engineers that into which politicians, lawyers,
accountants, and marketeers have poked their fingers.
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