DeTomaso Mailing List: July 98, Message #185

Mike,
Your are absouletly correct. The Job of the expansion valve is to
monitor the temperature of the evaporator. It will constantly adjust
itself to prevent the freezing of the evaporator coils. If the expansion
valve temperature probe is not correctly positioned in the coils of the
evaporator that could also cause the system to freeze up.

Cary

> ----------
> From: 	MikeLDrew@aol.com
> Reply To: 	MikeLDrew@aol.com
> Sent: 	Wednesday, July 01, 1998 6:35 PM
> To: 	Multiple recipients of list
> Subject: 	Re:  Compressor Cycling
> 
> Tim wrote:
> 
> >My AC has worked great for 7 or 8 years now.  My only complaint is
> that the
> system seems to cycle too often.  It blows really cold, but not for
> long
> enough before if cycles.  I wonder if there is any way to increase the
> cycle
> time that the compressor is on?
> 
> >>>Hmm.  I'm far from an A/C expert, but I'll give this one a shot,
> 'cause it
> saw it happen to P.J. Couillard.  His '72 had some funky hard lines in
> the
> system under the dash that you could see from the passenger seat.  We
> noticed
> the same thing happening, and I could see that the metal pipe would
> completely
> freeze over, then un-freeze, then freeze again...
> 
> The A/C would blow ice-cold for a few minutes until this hose froze
> over (and
> was blocked off), then it would quit until it warmed up and melted off
> (and
> dripped condensation all over my feet.)  Thus his system would cycle
> back and
> forth like yours does.  I think he replaced the expansion valve and
> cleaned
> (or discarded?) the screen and that solved it.
> 
> Might want to try having a passenger monitor the status of your hose
> (if
> visible) as you drive down the road.
> 
> Am I WAY, WAY out to lunch here guys?  (I'm sure you won't resist the
> temptation to tell me if I am! :>) )
> 
> Mike
>