Re: Climate Control--too much residual heat

[steveb@falcon.kla-tencor.com (Steven Buchholz)]

 # Another question about my new-used 88 5ktqw.  Can't get climate control
 # to give me straight vented air--always about 10-15 degrees F. more heat
 # added as it comes through the system.  Seems this must be a problem of
 # the system not closing down the heat valve completely--any suggestions?

I notice the same thing on my '88 5kCSQW.  It turns out that coolant 
flows through the heater core at all times except when the system is OFF 
or in "MAX AC" mode.  Even though the blend doors are supposed to be set 
to totally cut off any airflow through the heater core, I've gotta be-
lieve that this affects the temperature of the "pass through" air.  I 
suppose the original intention was that you'd drive with the A/C on all 
the time, and so it would be simple to precool the air to offset any 
heat from the heater core ... who knows.

It is getting to be the cool season again, so it won't matter so much to 
me, but I'll probably fit a manual heater valve next spring to allow me 
to control the amount of flow through the heater core separately from 
the HVAC's on/off valve.  

HTH!
Steve Buchholz
San Jose, CA (USA)