The Vanagon heater cores in comparison to the size of the engine are huge.
The rear heater is the same size as that in most cars. The front is 50 or
so larger. Yes, they can dissipate a lot of heat, especially at idle or no
load speeds. On a hot day wit the engine warm, suddenly open them both up
and put the fans on high. You will see the temp gauge drop for a short
while until the t-stat closes and the temp builds up again. Turning on the
heater is a common approach for many vehicles when the radiator can not do
the job.

Dennis

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Michael Elliott
Sent: Monday, December 03, 2007 1:53 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: New thermostat funky?

I'd suggest that if the thermostat is indeed closed so no heat is being
lost through the cooling system (heater doesn't dissipate that much heat,
does it?), then the engine has to be losing heat elsewhere. Surely there
is a minimum ambient temp that the engine can self-heat in? I reckon at
-300 degrees the engine could never get warm.

--
Mike "Rocket J Squirrel" Elliott
71 Type 2: the Wonderbus
84 Westfalia: Mellow Yellow ("The Electrical Banana")
74 Utility Trailer. Ladybug Trailer, Inc., San Juan Capistrano
KG6RCR

On 12/3/2007 10:09 AM Geza Polony wrote:

> Can someone explain this?
>
> "Even with the complete openings to the front of the radiator blocked
> off, it wouldn't run "normally" during the winter.  It still stayed
colder.
> I had to insulate all the plumbing under the van and around the engine
to
> get it to come close to normal on a cold, -20 degree F, day."
>
> Assuming the thermostat is completely closed, how come the engine won't
warm
> up? Shouldn't there be NO flow to the radiator with the t-stat closed?
>
> This is exactly what I would expect from mine (though I've never taken
it to
> 20* below)--and yet it indicates the cooling system is malfunctioning
even
> with a good thermostat, water pump, and all the rest.
>
> I'm baffled.