Re: Viper Fan Saab temperature switch

From: M.Bryan Galloway (mbggt@msn.com)
Date: Wed Apr 23 2003 - 10:03:07 EDT


This is supposed to be part of my previous post, Oooops.
I have two questions, one about the 2nd wiring diagram and the other about
the placement of the thermostatic switch.
1st: You drew the a/c fan control relay in series with the a/c comp clutch
relay. I think its possible that the combined resistance [impedance,
actually] MAY be sufficient to reduce current flow to the point that the
relays act erratically, or possibly that the voltage drop across the first
will cause the 2nd to go erratic. Wouldn't the coils in parallel off the pcm
provide full voltage/current to both and operate the way you want them to?
2nd: You said you installed the thermostatic switch in the upper radi
ator hose. Every liquid cooled volkswagen I've seen puts that switch in the
lower area of the radiator near the radiator outlet [lower hose]. Won't
placing a 180 switch just downstream of a 180 t-stat have the fan come on
when the t-stat opens? I believe the temp controls are set up to work in
stages; I.E. high temp leaving the engine opens the t-stat to provide
radiator cooling, high temp leaving the radiator enables the [low-speed] fan
circuit to increase radiator cooling, and continuing temp increase leaving
the radiator enables the the high-speed fan circuit. Won't having the switch
in the upper hose cause increased cycling of the t-stat/fan? These question
are purely theoretical as I haven't done the install myself, yet and I'm
trying to anticipate/head-off operational problems
M.Bryan Galloway

mbggt@hotmail.com

For any thinking person the title "Criminal Justice System" should have been
sufficient warning. L. Neil Smith

_________________________________________________________________
STOP MORE SPAM with the new MSN 8 and get 2 months FREE*
http://join.msn.com/?page=features/junkmail



This archive was generated by hypermail 2b29 : Fri Feb 06 2004 - 11:46:12 EST