Heating Question

[GTSHolgi]

I recently noticed, that I am not able to get any warm air out of the 3 outlets in the middle of the the dash. Only if I switch to the outlets above (windshield) or below (foot area) I notice warm air coming out. Of course, I tried when engine was at normal operating temperature and heater switch was at "full red". I have to add, that the heater fan is working and there is air blown out of the 3 outlets in the dash, hower it is always rather cold. When I switch on the A/C, the air coming out gets even colder.

Any idea? To me this does not seem normal, but as this is my first Viper (have it for a month now) I think it's worth asking the experts. Thanks a lot for your advise

Holger

 

[dave6666]

Heat only through knee bolster vents or defrost. By design. Ambient or AC only through dash vents. By design.

 

[Steve-Indy]

ONLY cold air will normally come from the 3 vents in the center of the dash...NEVER warm air from these locations unless A/C is broken.

Warm air ONLY comes from footwell area OR windshield area as you have described.

This is the way Gen I's and II's are built.

 

[GTSHolgi]

Wow, that's fast!!! Typical Viper

Thanks a lot for your answers, so it seems that everything is working fine! I read the owner's manual before but it does not say, that warm air will only come out of the defroster and/or knee bolster outlet...

To all of you: Have a great Sunday and enjoy your Viper! Here in Germany (in the area where I live) weather is terrible today, very windy and lots of rain....but I enjoyed the car yesterday, that will keep me up for a few days

Holger

 

[Steve-Indy]

One other point my own management of the HVAC controls in Gen I & II Vipers is covered in the following thread:

http://forums.viperclub.org/threads...n-passengers-air-vent-!?highlight=water+valve

 

[vettegc]

I don't have any warm air from the knee bolster vents? Doesn't blow at all when heat is on? The defroster vent blows warm! Cold air flows through it when the AC is on? Also didn't realize the middle vents weren't suppose to blow warm air. Good info!

 

[GTSHolgi]

Attached is an overview of the climate control modes taken from the Body Electrical Viper Student Workbook which I purchased on Ebay months after I started this thread. It helps to understand the logic of the system that sometimes confuses (me)

You must be registered for see images

Holger

 

[Sybil TF]

Heat only through knee bolster vents or defrost. By design. Ambient or AC only through dash vents. By design.

I was wondering about that just yesterday. I thought it was broke. Thanks for clearing that up!

 

[mattdillon]

Attached is an overview of the climate control modes taken from the Body Electrical Viper Student Workbook which I purchased on Ebay months after I started this thread. It helps to understand the logic of the system that sometimes confuses (me)

You must be registered for see images

Holger

Holgi, Thanks this is Perfect! jmo

 

[djviper]

Quick question, does the center temp knob on a gen 2 actually do anything? It doesn't seem to.

 

[LifeIsGood]

The way it should work according to the service manual is that settings to the left of center do not have temperature control; AC is cold and vent is simply ambient air. On the right the heat, defrost and mix do have temp control.

If you look at the diagram of the heater A/C unit (the box under the dash with the heater core, A/C evaporator, and venting doors) you see that air coming out of the dash vents and crotch holes doesn't pass through the heater core. Air coming out of the window defroster or floor ducts does pass through the heater core. Since the temperature is adjusted by how much coolant passes through the heater core (i.e. not blending cool and warm air) it will be slow to respond - have to wait until the coolant in the heater core cools down or heats up.

If it's going to be a DD, need to know these things.

...from an older thread.

 

[Viper98912]

interesting design....

 

[GTSHolgi]

BTW: One other thing I learned is, that the "Defrost" position always switches on the A/C. I noticed that because of the fan going on high speed and making more noise. Later I found a respective comment "hidden" in one of the student workbooks.

Holger

 

[djviper]

BTW: One other thing I learned is, that the "Defrost" position always switches on the A/C. I noticed that because of the fan going on high speed and making more noise. Later I found a respective comment "hidden" in one of the student workbooks.

Holger

That's not unusual, most cars switch on AC to defrost (dries the air).

The ultra-slow response of the middle temp setting dial was a mystery to me, glad someone finally explained it.

 

[GTSHolgi]

That's not unusual, most cars switch on AC to defrost (dries the air).

True. But usually, it's indicated by an additional light that A/C is on and you can typically switch it off, if you want but still direct air flow to the windshield. Don't get me wrong, I am not complaining at all. Actually it is fun to discover those small Viper "secrets" every once in a while

Holger