[DeTomaso] Useless technical Pantera factoid of the day

[Thomas Tornblom]

Charles McCall skrev:
> I discovered something while driving the Pantera to work today. 
>  
> I had always assumed that the heater valve in all Panteras was mechanical -
> ie you slide the little lever back and forth between hot and cold and you
> are physically opening and closing a valve allowing more coolant or less
> into the circuit. 
>  
> On the late-model Panteras, with the Maserati heater controls, it would
> appear that this is not the case. It would appear to be vacuum controlled.
> Here's what I discovered. 
>  
> Set the temperature slide for maximum heat and don't touch it. Push the
> button for "defrost". Hot air comes out the defrost thingies on the dash.
> Without touching the temp control, simply pushing the button for A/C but
> with the thermostat set so that the A/C won't turn on, the air that comes
> out the dash vents begins hot but quickly cools off. Pushing the button for
> "heat" makes hot air come out the vents again. 
>  
> Actually now that I type this, perhaps the heater valve is indeed mechanical
> but there are two air paths possible - In "defrost" and "heat", air comes
> from outside and passes through the heater core but in "Max A/C" air comes
> from inside the cabin and does not pass through the heater core? Anybody
> ever studied the HVAC system of the late model cars? What I found was
> curious was that you could have either hot or cold air coming out the vents
> without touching the temp control. 

There are two water valves, one mechanical and one vacuum controlled.

If you push the Max A/C button the vacuum controlled valve closes and 
thus the mechanical valve then is inoperable.

You can access the vacuum controlled valve if you remove the small cover 
above the heater on the passenger side in the front trunk.

>  
> Charles McCall
> 1985 DeTomaso Pantera GT5-S #9375
> "Raising Pantera Awareness across Europe"
> http://members.aol.com/PanteraGT5S1985/
> _______________________________________________

Cheers,
Thomas


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