Date: Mon, 4 Jan 1999 11:36:43 -0700
Reply-To: "Jon B. Kanas" <kanas@QUALITY.QADAS.COM>
Sender: Vanagon Mailing List <vanagon@vanagon.com>
From: "Jon B. Kanas" <kanas@QUALITY.QADAS.COM>
Subject: Behr Air Conditioning
Content-Type: TEXT/PLAIN; charset=US-ASCII
I have received several inquiries about the layout and configuration of
the Behr aftermarket air conditioning system installed in many Vanagons.
I have prepared the following (long) description that I hope will be
useful to some of my fellow Vanagon owners.
Behr of Germany makes primarily air conditioning systems and radiators.
They, like most German companies, make excellent products, some of which
have noteworthy flaws. They are a primary supplier to Mercedes, Porsche
and Volkswagen. I have seen units identical to mine in both water and
air-cooled Vanagons, and the installation is essentially identical. I
believe that they are quite common.
The unit in my 1987 Vanagon Syncro Westfalia consists of a rotary R-12
compressor, mounted on the usual VW brackets on the top at the LR corner
of the engine compartment. The compressor is belt-driven, the belt drives
the compressor only, no other items. The engine pulley has three belt
tiers (a/c, p/s, alternator & water pump). Access for replenishing and
checking the freon charge is via schrader valves adjacent to the
compressor, on top of the engine. It is an elegant installation, and does
not interfere with access to other items on the engine. Removal of the
water pump may require moving the compressor. I haven't had to address
this yet.
The condenser is mounted in front of the radiator. I suspect is the
factory condenser since it fits in the factory mounts, and is as large as
the radiator. On the air-cooled Vanagons, the condenser is also mounted
in the front, behind the plastic radiator grille and fresh air intake.
The receiver/dryer unit is placed immediately adjacent to the condenser,
and is accessible via the upper front grille of the Vanagon.
The evaporator is installed under the dashboard on the passenger's side.
The large plastic housing also encloses two three-speed blowers. The
housing extends below the dashboard, and requires removal of the top half
of the glove compartment enclosure, reducing the volume of the glove
compartment. Two drain hoses are located at the bottom of the enclosure,
connect below the enclosure via a 'Y' connector, with a single hose
exiting the interior of the Vanagon through a hole in the floor on the
front right corner of the passenger footwell. This plumbing is under the
passenger footwell carpet, and is not visible from the interior.
The blowers take in air from under the dashboard, blowing it into the
evaporator enclosure. There is a small duct at the top left of the
evaporator enclosure (maybe 30mm diameter) which directs air to a
dual-vent panel which is installed in the factory radio location. The two
hoses from the vents at the ends of the dashboard are disconnected from
the stock fresh air intake, and connected to fittings on the evaporator
enclosure. The stock fresh air intake is capped, and rendered inoperative
to these two vents.
A new housing for the radio is included with the system. The radio mounts
in the housing, the housing then attaches, vertically, to the plastic
heater outlet panel below the main dashboard. The quality of the
replacement radio housing is dubious, it is easily broken.
The system has one large power lead (maybe 10 gauge) which connects to an
ignition hot circuit. The system, as supplied by Behr, includes it's own
fuse block with 4 fuses. There is a fuse for the compressor, and one for
each fan. I do not remember the purpose of the fourth fuse; it may
control power to the cooling fan override circuit. On my Vanagon, this
fuseblock is located on the "tunnel" behind the heater duct panel. When
the radio is moved onto this panel, the radio must be removed before the
panel can be moved to access the fuses. There is a wire which in spliced
into the factory radiator cooling fan harness, downstream of the radiator
thermostat. The radiator cooling fan is activated via this circuit
whenever the compressor in engaged, to insure adequate airflow through the
condenser.
The air conditioning system has three controls; One for each fan and a
rheostat to control cooling. Low and Medium fan speeds are controlled by
directing current through appropriate wire resistors for each motor. The
rheostat varies the sensitivity of a thermal sensor in the evaporator
which engages and disengages the compressor to meet cooling demands.
History; Problems & Fixes:
My Vanagon Syncro was involved in a front-end collision before I bought it
in 1992. The overall repair job was excellent; I only figured out what
happened when I pulled the dashboard to install an alarm, replace the
speedometer cable and get one of the a/c blowers to work on low speed.
During replacement of the front sheet metal, the a/c system was
disconnected, and not properly rewired. I contacted Behr based on a label
I found on the system. They were very helpful, and provided me with
extensive documentation and troubleshooting assistance. They advised me
that they no longer make this system, and that many of the parts specific
to the aftermarket system are no longer available.
On my Vanagon, the weight of the radio frequently "unsnapped" the heater
outlet panel from the dashboard on rough roads. I solved this by drilling
inconspicuous holes in the heater ducts behind the outlet panel, and using
sheet metal screws with metal backplates to physically keep the outlet
panel in place. This has been an easy and effective fix; Behr should
have thought of this and advised to do this in their installation
procedures.
The Low and Medium fan speed resistor pack for fan motor #2 failed, and a
replacement part was not available. I fixed this by connecting the HIGH
setting of fan #2 to the HIGH circuit on fan #1 so that both fans are on
full blast when the fan #1 switch is on the HIGH position. The fan switch
for fan #2 has been removed, and replaced by a red LED which comes on
whenever the compressor is engaged. This helps me know if the compressor
is running when attempting to climb hills. If necessary, I can adjust the
temperature rheostat such that the compressor disengages so that maximum
power is available for propulsion. The fan(s) continue to run,
circulating residual cool air until I manually engage the compressor. I
found, this summer, on a long drive across the Eastern Colorado desert
that the fan switch was overheating when on high. It did OK with only one
fan, but two fans is overloading it. I will replace the switch and put a
relay into the HIGH fan circuit when I have the dashboard out to resolve
some unrelated problems.
The evaporator enclosure has cracked near one of the drain hoses, causing
water to drip into the passenger footwell. Hopefully some silicone seal
will address this.
The unit became discharged once during the six years I have owned it. One
of the schraeder valves in the engine compartment failed, allowing the
freon to leak out. The system was evacuated, re-lubricated and recharged
and has been subsequently trouble-free.
Advantages of Behr Aftermarket System:
1) No ceiling ducts, blowers or controls to fall on your head
2) No loss of overhead storage cabinet to rear evaporator as on factory
unit.
3) No auxiliary air intake imbedded in LR window.
4) Adequate on long trips in summer when cooling for extended period.
5) Recirculates interior air for maximum cooling efficiency.
6) Loss of fresh air ventilation capability at dash end vents.
7) Clean, inconspicuous installation.
Disadvantages of Behr Aftermarket System:
1) Only front passengers receive cooling. No direct ducts to rear of
Vanagon
2) Loss of approximately 1/2 glove compartment volume.
3) Placement of fuse panel behind dash panel is inconvenient.
4) Dual blowers loud when both on high.
5) Radio housing for remounting is easily damaged.
I hope that this information is of moderate usefulness!!
Jon B Kanas
Lockheed Martin Corporation
Flight Systems Spacecraft Test Lab
303-977-6354
jon.b.kanas@lmco.com
