Date:         Thu, 14 Jul 2005 23:01:10 -0400
Reply-To:     Don in North Carolina <vanagondon@GMAIL.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Don in North Carolina <vanagondon@GMAIL.COM>
Subject:      Re: AC converted to 134 - now what?
Comments: To: Jay Roth <bghuna@mchsi.com>
In-Reply-To:  <42D70CBA.10801@mchsi.com>
Content-Type: text/plain; charset=ISO-8859-1

On 7/14/05, Jay Roth <bghuna@mchsi.com> wrote:
> Volks:
> 
> Today I picked up the Westy from the shop from having the factory R12 AC
> converted to R134. Although the compressor is noisy, the diagnosis was
> that the high pressure hose was leaking, not the compressor as I
> anticipated.
> 
> Here's the concern:
> I turned on the van, pulled out of the parking lot, and turned on the
> AC. Drove 25 feet and the radiator fan (which is running on speed 2 as
> it should) jumps to speed 3. Of course, I check the gauges and notice
> the temp gauge hasn't moved yet and the AC compressor is still running.
> I recall that when the radiator fan ran at the highest speed, the
> compressor, when it was R12, would stop so as not to overheat the
> system. Concerned and curious, I drive it home through heavy stop & go
> traffic in summer heat of 90F and notice that the radiator fan cycles
> between med and high speeds. On the interstate I believe that it does
> *not* remain at high speed as it wasn't when I pulled onto the exit
> ramp. (An FYI - it does cool sufficiently).
> 
> My question is - with the higher pressure of R134, is this normal? Have
> all the other R134 converts had this same experience? Or has the ballast
> behind the driver's headlight ironically malfunctioned at the same time
> and need replacement? Or has the shop missed something that I can alert
> them to?
> 
> Advice sought soon so I can call the shop ASAP if necessary.
> 
> In *V*olkswagen *W*esty Love, Light, & Laughter,
> Jay
> '87 Westy
> Springfield, Missouri

Jay,

It sounds like it is working as designed, at least when you consider
"as designed" was for the lower R-12 pressures.

With the A/C on, the radiator fan runs at slow (Stage 1) speed.  When
the system detects a high refrigerant pressure (210.2 PSI) it switches
the fan to medium (Stage 2) speed.  When the pressure is reduced to
174 PSI, the high pressure switch opens and the fan returns to slow
speed.


That said, my '87 Syncro was converted to R-134, and the fan didn't
cycle on it...

-- 
Don in Reidsville, NC
1986 Kawasaki Concours
1988 Vanagon GL (Sylvia)
"Why do they call it a fixed income, if mine is always broke?"