Date: 18 Apr 97 01:31:33 EDT
Sender: Vanagon Mailing List <vanagon@vanagon.com>
From: "Clark M. Carr" <75716.763@CompuServe.COM>
Subject: RE: Auxillary Heater (Long)
I've now received several requests for these notes so I'm posting them to the
list.
On Wed, 16 Apr 1997 Matt Michael Lamar wrote:
> Clark,
> I would appreciate it if you could find your plans and post them either
> to the list or directly to me.
OK it goes to the list 'cause I've been really pleased with the way it works for
me. However the entire design and original idea belongs to David Garth. A
really nice guy, who even helped talk me through it since I'm not as handy as
most of the Listees. :) You guys impress me with what you know and are able to
do all the time. Really. Anyway, I didn't reach David to ask about sharing
this but it was posted in a Compuserve forum and I know he published it on his
Wep page with pictures at one point. He has done a bunch of goofy things to his
Westy but he had a very nice custom second battery installation that I saw and
he even worked a copper coil from the rear heater core that acted as an imersion
heater in his water tank. Claimed he could get 12 gallons of water in his water
tank to "shower temperature" by idleing the engine for 20 minutes. :)
Sorry for rambling. Here is his original post:
#: 86 S0/CompuServe Mail [MAIL]
28-Sep-94 07:29 PDT
Sb: heater review
Fm: David Garth [76176,762]
Catalytic Heater Review for VW Vanagon Camper
I have just completed the installation and testing of a catalytic
space heater in my 1986 VW Westfalia, and with winter coming up, I
thought my results might be of some interest. (Special thanks to
Derek Drew for information and inspiration.)
Two critical decisions must be made before proceeding with this
project: 1. What type of heater. 2. Where to put it.
After a great deal of research, I decided to buy a vented
catalytic heater from Thermal Systems, Inc. (2757 29th St.
Tumwater, WA 98512, 206-352-0539) I chose a catalytic heater
because it is much more efficient of both propane and 12 volt
current than any other type. Catalytics provide radiant heat, and
most of the energy in the propane is turned into useful heat.
Typical RV forced-air heaters consume about 4 amps of 12 volt current when
running, and send a lot of the heat out through their vent. Most
catalytic heaters are not vented. These unvented ones don't meet
the RV or any building codes, and, cause the user to keep at
least one window open for safety ventilation. Carbon monoxide
really does kill several thousand people a year, and I would
rather not take the chance. In addition, products of combustion
include a lot of water vapor. With an unvented heater, the water
vapor is trapped inside the vehicle, making it uncomfortably clammy,
and causing ice on the inside widows and condensation which
eventually causes body rust. (To the vehicle, not you.)
The Cat from Thermal systems is a different type of animal. It
uses a small, quiet 1/2 amp motorized blower to collect the
products of combustion, and then vents them outside through up to
12 feet of 1 1/2" flex hose or ridged ABS plastic pipe. The 12
volt connection also powers a microprocessor controlled safety
system that is really slick. If the vent is obstructed, there is
no gas supply, or there isn't enough oxygen, or the heater gets
too hot, or fails to light, or the 12 volt supply loses voltage,
the unit shuts down automatically. The unit is remotely
thermostatically controlled, and lights itself automatically.
When the thermostat calls for heat, an electric heating element
lights the gas without flame or spark. (The presence of the
platinum catalyst allows gas to react with oxygen at less than
normal flame temperature.)
Where to put it? I choose the larger 6000 btu unit because Derek
convinced me that the 3000 btu unit (both $279) would be too
small. I built a small cabinet, 28 inches high, 16 inches wide
and just 4 inches deep. I covered it in Formica (Desert Beige is
a perfect match) and installed it behind the passenger seat.)
This height lets the passenger seat fully recline even when all
the way back. The seat can still swivel, but the cabinet will be
slightly in the way when facing 100% backwards. The heater is
semi-recessed into this cabinet. The cabinet also hides the vent
hose, which goes up, left, down and through the vertical sheet
metal panel below the battery. The gas I tee'd off at the tank,
and ran 3/8 tubing over the gas tank to the right side, through
the same panel. I ran a new 12 gauge wire from the auxiliary
battery to the heater. Even though it only takes 1/2 amp when
running, it draws about 10 amps for about a minute when starting.
This isn't the only place one can put it, but I felt it was a
good compromise.
How well does it work? GREAT! It hasn t gotten cold enough here
in California to tell for sure, but the unit throws out LOTS of
radiant heat, with no odor and very little noise. Flick the
switch on the thermostat, wait about 2 minutes, and enjoy lots of
clean heat. Radiant heat is like a fireplace or camp fire, and
seems more pleasant than warming all the air in the vehicle. I
would rate the quality of the unit's construction and
engineering as excellent, except the sheet metal case is light
gauge and somewhat flexible. After installation this doesn t seem
to matter.
--David Garth
San Luis Obispo, CA
(I have no connection whatsoever with Thermal Systems or any of its emplyees.)
I must also report that my experience has been excellent with no problems at
all.
> Also, what was the cost of the heater?
It was about $350 including shipping when I bought it
> What year bus/vanagon did you install it in?
"Hilly" is a '90 Westfalia. Hope this helps and isn't too long for the list.
Regards, -Clark
pacocarr@mcimail.com