how AC clutch cycles? AC thermostat checking?

Konstantin Bogach kbogach@comcast.net
Tue, 01 Jul 2003 20:09:40 -0400


Measured  vent temperature today - 50F.   It is too low but I saw clutch
cycling.  What is most important to target - amount of refregirant or pressure?

Konstanatin.


Peter Golledge wrote:

> Konstantin,
>
> >From my limited experience you should be OK with 30 PSI on the low side.
> Did you have
> the radiator shroud panel in place?   Without this in place the rad fan wont
> do a good job
> cooling the condensor which in turn means the evap wont cool real well.  I
> would take the
> car for a spin with a temp gauge in the vents.
>
> Cheers
> --
> Peter Golledge.
>
> 89 200TQA (R134A converted... cool)
> 89 Saab 900i (R134A converted friggin freezing with no Cimate control)
> 79 930 Porsche (R12 waiting on a conversion)
> 87 LT1Q (No room for Aircon with the V8 motor in a 5K!)
>
> ----- Original Message -----
> From: "Konstantin Bogach" <kbogach@comcast.net>
> To: "Eric" <eric-audi.ql@mindspring.com>
> Cc: <quattro@audifans.com>
> Sent: Saturday, June 28, 2003 8:55 PM
> Subject: Re: how AC clutch cycles? AC thermostat checking?
>
> > The only misbehaviour, as I suspected, was "no cycling" after 10 min of
> > running.  When compressor is on low pressure is 30-32 psi, high pressure
> is
> > around 200psi.  The only numbers for low pressure I saw was great Peter's
> > Golledge post about conversion procedure.  It states 30-35 psi is a norm.
> I
> > got there right after third can of R-134A.
> >
> > Konstantin.
> >
> > Eric wrote:
> >
> > > As far as how much charge weight of refrigerant is more important than
> > > pressure.  Recommendations I have heard put the charge of R134a at
> > > around 80% of an R12 charge by weight.
> > >
> > > I have never put my manifold on my Audi (still works great with R12) as
> > > I don't want to mess with a good thing.  I have seen the numbers for my
> > > Suburban when I converted it.  Its low side pressure cycles between
> > > about 55-60 psi when off down to 25 psi when the compressor cycles off.
> > >
> > > Have you had guages on it when it misbehaves to see if something is
> > > changing before it happens?
> > >
> > > -Eric
> > >
> > > Konstantin Bogach wrote:
> > >
> > > >Hi.
> > > >I just finished AC conversion.  The leak I reported 2 days ago was
> > > >probably due to not tight connection at manifold and not tight low side
> > > >shreder valve.  I took 3 cans of R-134A with low side pressure at 30psi
> > > >and refused to take more when I tried to  raise it to 35psi.
> > > >
> > > >Now the problem (may be not):  after 10 min working at 90F outside
> > > >clutch does not cycle.  Does it look normal?
> > > >
> > > >I removed thermostat, hooked up DMM  and it shows 1.3 Ohm.  Shouldn't
> it
> > > >be short (0 Ohm)?
> > > >
> > > >Thanks.
> > > >Konstantin.
> > > >200tqa '89  (now with cool air!!!)
> > > >200tq '89  (will have cool air soon)
> > > >S4 '93  (did not nose anywhere yet, and air is cool.  Wierd!)
> > > >
> > > >
> > > >
> > > >
> >