Date:         Tue, 30 Aug 94 16:42:03 EDT
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         DerekDrew@aol.com
Subject:      Catalytic Heater

I have examined carefully the article Joel posted last month about catalytic
propane heaters for our vans and am coming to some conclusions: 

1. Catalytic heaters are probably preferable to non-catalytic heaters because
non-catalytic heaters lost up to 45% of the heat through the exhaust vent.
With our limited stocks of propane, I don't think we can afford this. 

2. A 6,000 btu unit seems about the right size for my 90 syncro westy which I
use in Vermont camping out in the mountains overnight. I think by experience
with coleman units that use screw in bottles I have determined that 6,000
btus is enough to heat the van to 72 degrees inside when it is about 30-35
degrees outside. Below that I intend to augment the 6,000 btus catalytic
heater with the coleman portable heater I just mentioned, the Black Cat
5,000.

3. Of the two major manufacturers of catalytic heaters, Olympian is more
widely advertised, and others on this list have said they use this brand. But
the other underdog? manufacturer, Thermal Systems, makes a catalytic heater
that is externally vented. Thus, you have no problems with air purity, you
don't have to crack a window, and you do not emit and spread moisture around
the inside of your camper/vanagon. The external venting does not robb heat
from the unit in the way that external venting on a standard heater would.  I
think I am therefore leaning toward getting the Thermal Systems brand which
is pushing a "sale" on their units until year-end. The 6,000 externally
vented unit I am looking at is on sale for $279.

There is a question as to how to rig the venting, but I am thinking of
venting through the battery compartment, as this has a vent leading under the
front passenger seat to the outside of the vehicle. Venting is by means of a
flexible 1.5" hose that may be cut to any length or even vented down through
the floor.

I suppose when I go to buy this unit I should band together with others on
this list if there are sufficient numbers in order to get an additional
discount from the manufactuer. --I am sure a bulk order for 10 units would be
quite attractive to them.

The heater consumes 1/4 of a gallon of propane per hour when operating at
full blast (it is thermostatically controlled, so this would only happen when
it is very cold out.). Thus, on a 3 gallon Vanagon tank you'd get 12 hours at
full blast. With two tanks (one mounted under the sliding door) as I have,
you'd get 24 hours at full blast. 

The unit consumes less than 1/2 amp per hour so it would probably take us 60
hours of use to seriously draw down our batteries in the event that we did
not start our cars to recharge them.

Thermal Systems sends stuff out on their heater on request and the number is
206-352-0539.

Questions, comments, fellow toasty campers?

derekdrew@aol.com