Date:         Thu, 23 Jan 97 10:55:26 -0600
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         Rocko Flamefart <-@--.-->
Subject:      Reefer Madness

so Tim Smith asks of boat reefers:

>Any reefer gurus want to explain to me how this could be plumbed and done in
>a van? (without any AC presently)

the boat reefers work wonderfully well.  in fact, their total amperage draw
for intermittantly running the compressor can nearly be met with
photovoltaics.  certainly with periodic running of the alternator.  the
units are compact, efficient, very well insulated, and nearly perfect except
for one minor difference.... they use a water cooled condensor.  this gives
them great efficiency as the heat transfer is 25 times greater in water than
air (or is *speed of sound* is 25 times greater in water than air, doesn't
matter-- it's better).  add to this a relatively cool heat transfer media
(Lake Superior water will always make 'boys of the best of men' :).

yet all is not lost.

there ARE marine reefer unit that utilize an air-cooled condensor.  in fact
there are units with selectable air/water cooling.  the price is paid in
running time and efficiency.  a typical air cooled unit will draw 5 amps
while running and needs to run about 50% of the time for a net use of 2.5
amps.  since the interior of a van is likely hotter than the ship cabin, i'd
bump the running time up to mebbe 75% for a net amperage draw of 3.75 amps.
this is walking the edge of photovoltaic output.  or a big MoFo battery.
and most of these are selectable for AC power too.  the cool thing about
many of these units is that they are sold to 'drop in' your existing or
custom insulated ice box.  very neat. very capable at serving about 220-360
BTUs of heat removal per hour @ 20F evaporator temp.

prices run on these units from $500-$1000.  that's alot of propane i can buy
to run the Dometic.  course, i may die from food spoilage, but hey, i saved
a buck, right?

-dan (not a Reefer Guru, just read the West Marine catalog too much.)