When I first built the van I decided that
I wanted to have air conditioning. This was
supposed to be my daily driver when the Corrado
was broken. Then I had to get a winter daily
because the van was too valuable to trash
in the winter time. In either event, daily
drivers require frosty cold AC and the Vanagon
was no exception.
I originally tried to do electric AC in here
10 years ago using a 7,000 BTU room AC unit.
It worked rather poorly and I was able to
take away from it three key learning experiences:
First was that these room AC units are terribly
inefficient, espescially when they are the
single ducted model which was what I had.
Some of the chilled air is then used to cool
the condenser coil and that hot air is then
rejected outside. This means that air needs
to be replenished from somewhere, which means
that hot air gets pulled in from outside!
Technology connections did a great video explaining
this in detail and I recommend checking it
out. I’ll also put a link in the description.
At the time I was using a room unit that was
somewhere around 7,000BTU and this drew about
900 watts of 120volts AC to power, which translated
to 100 amps of draw. This quickly ruined an
alternator when I used one alternator to power
that and the rest of the van. I thought about
installing a second alternator which would
have solved the problem I think, combined
with using a double ducted or mini split type
unit.
While a 7,000BTU room air conditioner may
work well for a 12x12 room, this is utterly
terrible for vehicles. To cool a small house
AC will be somewhere around 24,000BTU, or
2 tons. A Chevy Suburban can have AC that
exceeds 60,000BTU, or 5 tons in capacity!
The reason for all the extra tonnage is because
the sun is a powerful adversary to keeping
things chilled, at 1200watts per square meter;
the Suns rays pierce metal and glass with
ease. Since the van is half glass, this meant
that my electrified solution would be terribly
anemic at Its very best efficiency.
When I swapped the Subaru EG33 engine in,
I kept the components for the Air Conditioning
from the SVX I harvested the original engine
from, and kept much of the stock van stuff
as well. In the 2WD 7 passenger Vanagons as
mine originally was, the evaporator unit was
overhead near the center of the van between
the front two seats and the rear area. I have
seen some Westfalia Vanagons where the evaporator
unit is located in the very back which I decided
to mimic because I liked having all the overhead
room up front. When you don’t have anything
mounted near the ceiling it really makes a
difference when it comes to feeling spacious.
My original one was falling down, so I removed
it all knowing that I would replace it with
something else later on. One night browsing
around on eBay I found an evaporator box that
is a sort of universal fit and it was a good
price. I decided to give it a shot on my van,
the BTU rating was somewhere around 35,000
I think. The evaporator was large, much larger
than something you would see in a standard
heater box located inside the dash panel.
At the time I was unable to buy the newer
model condenser that is available from GoWesty,
so I was forced to locate a factory condenser
and run that for the time being.
The factory condenser is a “serpentine”
style heat exchanger, meaning that there is
one long continuous tube coiled up that refrigerant
flows through. The newer style condenser that
is more efficient is a “parallel flow”
condenser. These have multiple tubes in rows
that carry refrigerant from one side of the
heat exchanger to the other, and is the style
offered up from GoWesty. After waiting for
more than a year I was finally able to secure
one of my own, though I was a little disappointed
when it showed up and the condenser was anything
but “straight”. The price was right though,
so I cannot complain too much.
Another thing that needed an upgrade was the
Radiator fan. When I didn’t have air conditioning,
the early style three bladed 12-inch fan worked
okay for keeping the extra 180HP worth of
engine cool. When I had studied other EG swapped
Vanagons, people who did have AC found they
needed to upgrade to keep things cool, and
I was finally running up against this with
my new upgrades.
The original fan was 300 watts on the high
speed, and now this new one is 500 watts!
This fan shroud is from a diesel Vanagon,
and the fan itself is 14 inches in diameter
instead of 12! I am sort of apprehensive about
how tight the fitment is going to be, because
the 12 inch fan takes up almost all the space
in the cavity available for the fan to reside
in. I feel like things are going to get tight
when it comes installation time.
With the other two items a requirement on
the upgrade venture, it only makes sense to
complete the thermal transfer sandwich with
a new radiator. This is a Behr unit which
actually makes the OEM radiators for the Vanagon!
These come with the official VW part number
and logo scratched off of them. I decided
to put some epoxy over where the plastic has
been gouged to avoid potential failure of
a weak point later on down the road.
I wasn’t satisfied at all with the brackets
that come with the condenser in the GoWesty
kit. The brackets attach the condenser to
the van body which is different than the factory
mounting which attaches it the radiator. For
some people, I could totally see the GoWesty
kit being the better option since you might
be able to get away with not having to discharge
the AC should you need to service the radiator
or fan.
The problem that I see with this is that it
leaves a larger gap between the condenser
and radiator, and without any kind of air
dam or ducting to funnel the air being sucked
into radiator across the condenser before
hand, this can greatly effect overall AC system
efficiency and performance. I decided to make
my own brackets which would only take an afternoon.
I started with a CAD template and cut out
4 similar pieces out of an old server case
that I had laying around. Next I bent them
up and drilled the bolt hole, having a tab
that also inserts into the slot at all four
corners.
You’ll notice that the condenser is closer
to the radiator at the end that doesn’t
have the fittings. This is intentional as
there is a crash beam that essentially “cuts”
the radiator into a top and bottom section.
On the older vans the condenser was two piece,
on the later vans, it was a one piece condenser.
One thing I’ve realized though, is that
when you have some space between the beam
and the heat exchangers, more air can get
in and efficiency is increased greatly. That
is why I think I’ve never had any cooling
problems before I had AC, because I had the
condenser removed as well. There was almost
2 inches between the face of the radiator
and the crash beam and this allowed much greater
airflow throughout the entirety of the radiator.
To finish up this installation after bolting
the condenser down it was time for sealing
up any air paths between the condenser and
the radiator. To maximize efficiency of our
new found parallel flow condenser we need
to use some foil tape or sheet metal and seal
all the air gaps. This forces all cooling
air to pass through the first heat exchanger
before the radiator and finally the fan.
With the exchanger sandwich successfully assembled
it is time to move on to what we will be doing
for electrical controls, which requires a
separate video. Until next time, stay safe
and build your dreams!
